diff --git a/docs/NEWS.md b/docs/NEWS.md
index 0409f3f..f53a80a 100644
--- a/docs/NEWS.md
+++ b/docs/NEWS.md
@@ -1,5 +1,6 @@
 ### UNRELEASED
 
+ * feature: new "`--store-and-forward`" option to read input to a file first, then write it to the output ([#100](https://codeberg.org/a-j-wood/pv/issues/100))
  * feature: new "`--stats`" option to show transfer stats at the end, like "`ping`" ([#49](https://codeberg.org/a-j-wood/pv/issues/49))
  * feature: "`--rate`" can now be used with "`--numeric`" ([#17](https://codeberg.org/a-j-wood/pv/issues/17))
  * feature: "`--gauge`" with "`--progress`" to show rate gauge when size is unknown ([#46](https://codeberg.org/a-j-wood/pv/issues/46))
diff --git a/docs/pv.1 b/docs/pv.1
index 095d971..5882b8b 100644
--- a/docs/pv.1
+++ b/docs/pv.1
@@ -491,6 +491,30 @@ except that
 is never called.  Implies
 .BR \-C .
 .TP
+.BI \-U\  FILE \fR,\ \fB\-\-store\-and\-forward\  FILE
+Instead of passing data through immediately, do it in two stages - first
+read all input and write it to
+.IR FILE ,
+and then once the input is exhausted, read all of
+.I FILE
+and write it to the output.
+.I FILE
+remains in place afterwards, unless it is
+"\fB-\fR", in which case
+.B pv
+creates a temporary file for this purpose, and automatically removes it
+afterwards.
+.TP
+.B ""
+This can be useful if you have a pipeline which generates data (your
+input) quickly but you don't know the size, and you wish to pass it to some
+slower process, once all of the input has been generated and you know its
+size, so you can see its progress.  Note that when doing this with
+relatively small amounts of data,
+.B \-\-no-splice
+may be preferable so that pipe buffering doesn't affect the progress
+display.
+.TP
 .BI \-d\  PID\fR[\fB:\fR\fIFD\fR],\  \fB\-\-watchfd\  PID\fR[\fB:\fR\fIFD\fR]
 Instead of transferring data, watch file descriptor
 .I FD
diff --git a/docs/pv.1.md b/docs/pv.1.md
index 49ab081..53a519c 100644
--- a/docs/pv.1.md
+++ b/docs/pv.1.md
@@ -364,6 +364,23 @@ display types that are explicitly switched on will be shown.
     This is equivalent to redirecting standard output to */dev/null*,
     except that **write**(2) is never called. Implies **-C**.
 
+**-U FILE, \--store-and-forward FILE**
+
+:   Instead of passing data through immediately, do it in two stages -
+    first read all input and write it to *FILE*, and then once the input
+    is exhausted, read all of *FILE* and write it to the output. *FILE*
+    remains in place afterwards, unless it is \"**-**\", in which case
+    **pv** creates a temporary file for this purpose, and automatically
+    removes it afterwards.
+
+:   This can be useful if you have a pipeline which generates data (your
+    input) quickly but you don\'t know the size, and you wish to pass it
+    to some slower process, once all of the input has been generated and
+    you know its size, so you can see its progress. Note that when doing
+    this with relatively small amounts of data, **\--no-splice** may be
+    preferable so that pipe buffering doesn\'t affect the progress
+    display.
+
 **-d PID\[:FD\], \--watchfd PID\[:FD\]**
 
 :   Instead of transferring data, watch file descriptor *FD* of process
diff --git a/po/de.po b/po/de.po
index 3aa0f06..21d95a3 100644
--- a/po/de.po
+++ b/po/de.po
@@ -1,7 +1,7 @@
 msgid ""
 msgstr ""
 "Report-Msgid-Bugs-To: pv@ivarch.com\n"
-"POT-Creation-Date: 2024-10-04 22:08+0100\n"
+"POT-Creation-Date: 2024-10-05 16:04+0100\n"
 "PO-Revision-Date: 2024-09-29 11:07+0000\n"
 "Last-Translator: a-j-wood <a-j-wood@users.noreply.translate.codeberg.org>\n"
 "Language-Team: German <https://translate.codeberg.org/projects/pv/pv/de/>\n"
@@ -169,7 +169,8 @@ msgstr ""
 msgid "use cursor positioning escape sequences"
 msgstr "benutze Escape-Sequenzen zur Cursor-Positionierung"
 
-#: src/main/help.c:369 src/main/help.c:405 src/main/help.c:420
+#: src/main/help.c:369 src/main/help.c:399 src/main/help.c:408
+#: src/main/help.c:423
 msgid "FILE"
 msgstr "DATEI"
 
@@ -222,117 +223,125 @@ msgid "discard input instead of writing to output"
 msgstr "verwirf die Eingabe anstatt in die Ausgabe zu schreiben"
 
 #: src/main/help.c:400
+msgid "write all input to FILE before writing to output"
+msgstr ""
+
+#: src/main/help.c:403
 msgid "PID"
 msgstr "PID"
 
-#: src/main/help.c:401
+#: src/main/help.c:404
 msgid "update settings of process PID"
 msgstr "Einstellungen der Prozess-PID updaten"
 
-#: src/main/help.c:406
+#: src/main/help.c:409
 msgid "save process ID in FILE"
 msgstr "Prozess-ID in DATEI speichern"
 
-#: src/main/help.c:409
+#: src/main/help.c:412
 msgid "PID[:FD]"
 msgstr "PID[:FD]"
 
-#: src/main/help.c:410
+#: src/main/help.c:413
 msgid "watch file FD opened by process PID"
 msgstr "die vom Prozess PID geöffnete Datei FD beobachten"
 
-#: src/main/help.c:414
+#: src/main/help.c:417
 msgid "show this help and exit"
 msgstr "zeige diese Hilfe und beende"
 
-#: src/main/help.c:417
+#: src/main/help.c:420
 msgid "show version information and exit"
 msgstr "zeige Versionsinformationen und beende"
 
-#: src/main/help.c:421
+#: src/main/help.c:424
 msgid "write debug logs to FILE"
 msgstr "schreibe Debug-Protokolle in DATEI"
 
-#: src/main/help.c:446
+#: src/main/help.c:449
 #, c-format
 msgid "Usage: %s [OPTION] [FILE]..."
 msgstr "Aufruf: %s [OPTION] [DATEI]..."
 
-#: src/main/help.c:457
+#: src/main/help.c:460
 msgid ""
 "Concatenate FILE(s), or standard input, to standard output, with monitoring."
 msgstr ""
 "Verbindet DATEI(en) oder den Standard-Eingabe-Kanal mit dem Standard-Ausgabe-"
 "Kanal und misst den Datenstrom."
 
-#: src/main/help.c:594
+#: src/main/help.c:597
 #, c-format
 msgid "Please report any bugs to: %s"
 msgstr "Bitte senden Sie Fehlerberichte an %s"
 
-#: src/main/main.c:71
+#: src/main/main.c:214
+msgid "(input)"
+msgstr ""
+
+#: src/main/main.c:299
 msgid "state allocation failed"
 msgstr "Speicherzuweisung für `state' fehlgeschlagen"
 
-#: src/main/options.c:138 src/pv/file.c:324
+#: src/main/options.c:140 src/pv/file.c:324
 msgid "failed to stat file"
 msgstr "konnte Dateiinformationen nicht lesen"
 
-#: src/main/options.c:152
+#: src/main/options.c:154
 msgid "is a directory"
 msgstr "ist ein Verzeichnis"
 
-#: src/main/options.c:181
+#: src/main/options.c:183
 msgid "failed to generate sysfs filename"
 msgstr "konnte Sysfs-Dateinamen nicht erzeugen"
 
-#: src/main/options.c:203
+#: src/main/options.c:205
 msgid "failed to read sysfs size file"
 msgstr "konnte Größe der Sysfs-Datei nicht lesen"
 
-#: src/main/options.c:223
+#: src/main/options.c:225
 msgid "failed to open block device"
 msgstr "konnte Blockgerät nicht öffnen"
 
-#: src/main/options.c:233
+#: src/main/options.c:235
 msgid "failed to determine size of block device"
 msgstr "konnte Größe des Blockgeräts nicht ermitteln"
 
-#: src/main/options.c:336
+#: src/main/options.c:339
 msgid "option structure allocation failed"
 msgstr "Speicherzuweisung für `option' fehlgeschlagen"
 
-#: src/main/options.c:355
+#: src/main/options.c:358
 msgid "option structure argv allocation failed"
 msgstr "Speicherzuweisung für `argv' der Option fehlgeschlagen"
 
-#: src/main/options.c:417
+#: src/main/options.c:420
 msgid "integer argument expected"
 msgstr "Ganzzahliges Argument erwartet"
 
-#: src/main/options.c:428
+#: src/main/options.c:431
 msgid "numeric argument expected"
 msgstr "numerisches Argument erwartet"
 
-#: src/main/options.c:439
+#: src/main/options.c:442
 msgid "process ID or pid:fd pair expected"
 msgstr "Prozess-ID oder PID:FD-Paar erwartet"
 
-#: src/main/options.c:446
+#: src/main/options.c:449
 msgid "invalid process ID"
 msgstr "ungültige Prozess-ID"
 
-#: src/main/options.c:655
+#: src/main/options.c:666
 #, c-format
 msgid "Try `%s --help' for more information."
 msgstr "`%s --help' zeigt weitere Informationen an."
 
-#: src/main/options.c:657
+#: src/main/options.c:668
 #, c-format
 msgid "Try `%s -h' for more information."
 msgstr "`%s -h' zeigt weitere Informationen an."
 
-#: src/main/options.c:688
+#: src/main/options.c:699
 msgid ""
 "cannot use line mode or transfer modifier options when watching file "
 "descriptors"
@@ -340,24 +349,24 @@ msgstr ""
 "Beim Beobachten von Dateideskriptoren können keine Optionen für den "
 "Zeilenmodus oder den Übertragungsmodifikator verwendet werden"
 
-#: src/main/options.c:697
+#: src/main/options.c:708
 msgid "cannot use cursor positioning when watching file descriptors"
 msgstr ""
 "Beim Beobachten von Dateideskriptoren kann Cursor-Positionierung nicht "
 "verwendet werden"
 
-#: src/main/options.c:706
+#: src/main/options.c:717
 msgid "cannot use remote control when watching file descriptors"
 msgstr ""
 "Beim Beobachten von Dateideskriptoren kann die Fernbedienung nicht verwenden "
 "werden"
 
-#: src/main/options.c:715
+#: src/main/options.c:726
 msgid "cannot transfer files when watching file descriptors"
 msgstr ""
 "Beim Beobachten von Dateideskriptoren können Dateien nicht übertragen werden"
 
-#: src/main/options.c:730
+#: src/main/options.c:741
 msgid "not available on systems without /proc/self/fdinfo"
 msgstr "Nicht verfügbar auf Systemen ohne /proc/self/fdinfo"
 
@@ -401,45 +410,45 @@ msgstr "Sperrversuch fehlgeschlagen"
 msgid "failed to open terminal"
 msgstr "konnte Terminal nicht öffnen"
 
-#: src/pv/display.c:216
+#: src/pv/display.c:230
 msgid "yzafpnum kMGTPEZY"
 msgstr "yzafpnµm kMGTPEZY"
 
-#: src/pv/display.c:234
+#: src/pv/display.c:248
 msgid "yzafpnum KMGTPEZY"
 msgstr "yzafpnµm KMGTPEZY"
 
-#: src/pv/display.c:661 src/pv/transfer.c:970
+#: src/pv/display.c:675 src/pv/transfer.c:970
 msgid "buffer allocation failed"
 msgstr "Speicherzuweisung für den Puffer fehlgeschlagen"
 
-#: src/pv/display.c:790
+#: src/pv/display.c:804
 msgid "b"
 msgstr "b"
 
-#: src/pv/display.c:793 src/pv/transfer.c:602
+#: src/pv/display.c:807 src/pv/transfer.c:602
 msgid "B"
 msgstr "B"
 
-#: src/pv/display.c:837 src/pv/display.c:852 src/pv/display.c:1071
-#: src/pv/loop.c:418
+#: src/pv/display.c:851 src/pv/display.c:866 src/pv/display.c:1085
+#: src/pv/loop.c:494
 msgid "b/s"
 msgstr "b/s"
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
 msgid "/s"
 msgstr "/s"
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
-#: src/pv/loop.c:418
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
+#: src/pv/loop.c:494
 msgid "B/s"
 msgstr "B/s"
 
-#: src/pv/display.c:884 src/pv/display.c:888
+#: src/pv/display.c:898 src/pv/display.c:902
 msgid "ETA"
 msgstr "ETA"
 
-#: src/pv/display.c:954
+#: src/pv/display.c:968
 msgid "FIN"
 msgstr ""
 
@@ -471,15 +480,15 @@ msgstr "(keine)"
 msgid "(stdin)"
 msgstr "(stdin)"
 
-#: src/pv/loop.c:417
+#: src/pv/loop.c:493
 msgid "rate min/avg/max/mdev"
 msgstr ""
 
-#: src/pv/loop.c:429
+#: src/pv/loop.c:505
 msgid "rate not measured"
 msgstr ""
 
-#: src/pv/loop.c:635 src/pv/loop.c:686 src/pv/loop.c:727 src/pv/watchpid.c:99
+#: src/pv/loop.c:711 src/pv/loop.c:762 src/pv/loop.c:803 src/pv/watchpid.c:99
 #: src/pv/watchpid.c:109 src/pv/watchpid.c:120 src/pv/watchpid.c:128
 #: src/pv/watchpid.c:165 src/pv/watchpid.c:184 src/pv/watchpid.c:192
 #: src/pv/watchpid.c:202 src/pv/watchpid.c:293 src/pv/watchpid.c:301
@@ -491,7 +500,7 @@ msgstr "pid"
 msgid "history structure allocation failed"
 msgstr "Speicherzuweisung für `history' fehlgeschlagen"
 
-#: src/pv/state.c:470 src/pv/state.c:481
+#: src/pv/state.c:501 src/pv/state.c:512
 msgid "file list allocation failed"
 msgstr "Speicherzuweisung für die Dateiliste fehlgeschlagen"
 
diff --git a/po/fr.po b/po/fr.po
index 128cec1..fbe7a1d 100644
--- a/po/fr.po
+++ b/po/fr.po
@@ -1,7 +1,7 @@
 msgid ""
 msgstr ""
 "Report-Msgid-Bugs-To: pv@ivarch.com\n"
-"POT-Creation-Date: 2024-10-04 22:08+0100\n"
+"POT-Creation-Date: 2024-10-05 16:04+0100\n"
 "Language: fr\n"
 "Content-Type: text/plain; charset=UTF-8\n"
 "Date: 1999-06-01 15:18:29+0100\n"
@@ -162,7 +162,8 @@ msgstr ""
 msgid "use cursor positioning escape sequences"
 msgstr "utiliser les séquences d'échappements de positionnement de curseur"
 
-#: src/main/help.c:369 src/main/help.c:405 src/main/help.c:420
+#: src/main/help.c:369 src/main/help.c:399 src/main/help.c:408
+#: src/main/help.c:423
 msgid "FILE"
 msgstr "FICHIER"
 
@@ -215,117 +216,125 @@ msgid "discard input instead of writing to output"
 msgstr "rejeter l'entrée au lieu de l'écrire vers la sortie"
 
 #: src/main/help.c:400
+msgid "write all input to FILE before writing to output"
+msgstr ""
+
+#: src/main/help.c:403
 msgid "PID"
 msgstr "PID"
 
-#: src/main/help.c:401
+#: src/main/help.c:404
 msgid "update settings of process PID"
 msgstr "mettre à jour la configuration du processus PID"
 
-#: src/main/help.c:406
+#: src/main/help.c:409
 msgid "save process ID in FILE"
 msgstr "enregistrer l'ID de processus dans FICHIER"
 
-#: src/main/help.c:409
+#: src/main/help.c:412
 msgid "PID[:FD]"
 msgstr "PID[:FD]"
 
-#: src/main/help.c:410
+#: src/main/help.c:413
 msgid "watch file FD opened by process PID"
 msgstr "surveiller le fichier FD ouvert par le processus PID"
 
-#: src/main/help.c:414
+#: src/main/help.c:417
 msgid "show this help and exit"
 msgstr "afficher cette aide puis quitter"
 
-#: src/main/help.c:417
+#: src/main/help.c:420
 msgid "show version information and exit"
 msgstr "afficher la version puis quitter"
 
-#: src/main/help.c:421
+#: src/main/help.c:424
 msgid "write debug logs to FILE"
 msgstr "écrire les journaux de déboggage vers FICHIER"
 
-#: src/main/help.c:446
+#: src/main/help.c:449
 #, c-format
 msgid "Usage: %s [OPTION] [FILE]..."
 msgstr "Utilisation : %s [OPTIONS] [FICHIER]..."
 
-#: src/main/help.c:457
+#: src/main/help.c:460
 msgid ""
 "Concatenate FILE(s), or standard input, to standard output, with monitoring."
 msgstr ""
 "Concaténer FICHIER(s), ou l'entrée standard, sur la sortie standard avec "
 "monitorage."
 
-#: src/main/help.c:594
+#: src/main/help.c:597
 #, c-format
 msgid "Please report any bugs to: %s"
 msgstr "SVP rapporter tous bogues à %s"
 
-#: src/main/main.c:71
+#: src/main/main.c:214
+msgid "(input)"
+msgstr ""
+
+#: src/main/main.c:299
 msgid "state allocation failed"
 msgstr "échec de l'allocation de mémoire de condition"
 
-#: src/main/options.c:138 src/pv/file.c:324
+#: src/main/options.c:140 src/pv/file.c:324
 msgid "failed to stat file"
 msgstr "échec à statuer sur le fichier"
 
-#: src/main/options.c:152
+#: src/main/options.c:154
 msgid "is a directory"
 msgstr ""
 
-#: src/main/options.c:181
+#: src/main/options.c:183
 msgid "failed to generate sysfs filename"
 msgstr ""
 
-#: src/main/options.c:203
+#: src/main/options.c:205
 msgid "failed to read sysfs size file"
 msgstr ""
 
-#: src/main/options.c:223
+#: src/main/options.c:225
 msgid "failed to open block device"
 msgstr ""
 
-#: src/main/options.c:233
+#: src/main/options.c:235
 msgid "failed to determine size of block device"
 msgstr ""
 
-#: src/main/options.c:336
+#: src/main/options.c:339
 msgid "option structure allocation failed"
 msgstr "l'allocation pour la structure d'une option a échoué"
 
-#: src/main/options.c:355
+#: src/main/options.c:358
 msgid "option structure argv allocation failed"
 msgstr "l'allocation pour la structure de l'option argv a échoué"
 
-#: src/main/options.c:417
+#: src/main/options.c:420
 msgid "integer argument expected"
 msgstr "Valeur entière attendue"
 
-#: src/main/options.c:428
+#: src/main/options.c:431
 msgid "numeric argument expected"
 msgstr "Valeur numérique attendue"
 
-#: src/main/options.c:439
+#: src/main/options.c:442
 msgid "process ID or pid:fd pair expected"
 msgstr "ID de processus ou paire pid:fd attendue"
 
-#: src/main/options.c:446
+#: src/main/options.c:449
 msgid "invalid process ID"
 msgstr "ID de processus non valide"
 
-#: src/main/options.c:655
+#: src/main/options.c:666
 #, c-format
 msgid "Try `%s --help' for more information."
 msgstr "Essayez `%s --help' pour plus d'informations."
 
-#: src/main/options.c:657
+#: src/main/options.c:668
 #, c-format
 msgid "Try `%s -h' for more information."
 msgstr "Essayez `%s -h' pour plus d'informations."
 
-#: src/main/options.c:688
+#: src/main/options.c:699
 msgid ""
 "cannot use line mode or transfer modifier options when watching file "
 "descriptors"
@@ -333,25 +342,25 @@ msgstr ""
 "impossible d'utiliser le mode ligne ou les options de modificateur de "
 "transfert lors de la visualisation des descripteurs de fichiers"
 
-#: src/main/options.c:697
+#: src/main/options.c:708
 msgid "cannot use cursor positioning when watching file descriptors"
 msgstr ""
 "impossible d'utiliser le positionnement du curseur lors de la visualisation "
 "des descripteurs de fichier"
 
-#: src/main/options.c:706
+#: src/main/options.c:717
 msgid "cannot use remote control when watching file descriptors"
 msgstr ""
 "impossible d'utiliser la télécommande lors de la visualisation des "
 "descripteurs de fichiers"
 
-#: src/main/options.c:715
+#: src/main/options.c:726
 msgid "cannot transfer files when watching file descriptors"
 msgstr ""
 "impossible de transférer des fichiers lorsque vous regardez des descripteurs "
 "de fichiers"
 
-#: src/main/options.c:730
+#: src/main/options.c:741
 msgid "not available on systems without /proc/self/fdinfo"
 msgstr "non disponible sur les systèmes sans /proc/self/fdinfo"
 
@@ -397,45 +406,45 @@ msgstr "échec de la tentative de verrouillage"
 msgid "failed to open terminal"
 msgstr "échec de l'ouverture du terminal"
 
-#: src/pv/display.c:216
+#: src/pv/display.c:230
 msgid "yzafpnum kMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:234
+#: src/pv/display.c:248
 msgid "yzafpnum KMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:661 src/pv/transfer.c:970
+#: src/pv/display.c:675 src/pv/transfer.c:970
 msgid "buffer allocation failed"
 msgstr "échec de l'allocation de mémoire tampon"
 
-#: src/pv/display.c:790
+#: src/pv/display.c:804
 msgid "b"
 msgstr ""
 
-#: src/pv/display.c:793 src/pv/transfer.c:602
+#: src/pv/display.c:807 src/pv/transfer.c:602
 msgid "B"
 msgstr "O"
 
-#: src/pv/display.c:837 src/pv/display.c:852 src/pv/display.c:1071
-#: src/pv/loop.c:418
+#: src/pv/display.c:851 src/pv/display.c:866 src/pv/display.c:1085
+#: src/pv/loop.c:494
 msgid "b/s"
 msgstr ""
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
 msgid "/s"
 msgstr "/s"
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
-#: src/pv/loop.c:418
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
+#: src/pv/loop.c:494
 msgid "B/s"
 msgstr "O/s"
 
-#: src/pv/display.c:884 src/pv/display.c:888
+#: src/pv/display.c:898 src/pv/display.c:902
 msgid "ETA"
 msgstr "ETA"
 
-#: src/pv/display.c:954
+#: src/pv/display.c:968
 msgid "FIN"
 msgstr ""
 
@@ -467,15 +476,15 @@ msgstr "(aucun)"
 msgid "(stdin)"
 msgstr ""
 
-#: src/pv/loop.c:417
+#: src/pv/loop.c:493
 msgid "rate min/avg/max/mdev"
 msgstr ""
 
-#: src/pv/loop.c:429
+#: src/pv/loop.c:505
 msgid "rate not measured"
 msgstr ""
 
-#: src/pv/loop.c:635 src/pv/loop.c:686 src/pv/loop.c:727 src/pv/watchpid.c:99
+#: src/pv/loop.c:711 src/pv/loop.c:762 src/pv/loop.c:803 src/pv/watchpid.c:99
 #: src/pv/watchpid.c:109 src/pv/watchpid.c:120 src/pv/watchpid.c:128
 #: src/pv/watchpid.c:165 src/pv/watchpid.c:184 src/pv/watchpid.c:192
 #: src/pv/watchpid.c:202 src/pv/watchpid.c:293 src/pv/watchpid.c:301
@@ -487,7 +496,7 @@ msgstr ""
 msgid "history structure allocation failed"
 msgstr "l'allocation de la structure de l'historique a échoué"
 
-#: src/pv/state.c:470 src/pv/state.c:481
+#: src/pv/state.c:501 src/pv/state.c:512
 msgid "file list allocation failed"
 msgstr "échec de l'allocation de la liste de fichiers"
 
diff --git a/po/pl.po b/po/pl.po
index ffddd4d..efe9e41 100644
--- a/po/pl.po
+++ b/po/pl.po
@@ -6,7 +6,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: pv@ivarch.com\n"
-"POT-Creation-Date: 2024-10-04 22:08+0100\n"
+"POT-Creation-Date: 2024-10-05 16:04+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -155,7 +155,8 @@ msgstr "pokaż wyjście nawet gdy błędy nie są typu terminal"
 msgid "use cursor positioning escape sequences"
 msgstr "używaj sekwencji escape do pozycjonowania"
 
-#: src/main/help.c:369 src/main/help.c:405 src/main/help.c:420
+#: src/main/help.c:369 src/main/help.c:399 src/main/help.c:408
+#: src/main/help.c:423
 msgid "FILE"
 msgstr ""
 
@@ -208,135 +209,143 @@ msgid "discard input instead of writing to output"
 msgstr ""
 
 #: src/main/help.c:400
+msgid "write all input to FILE before writing to output"
+msgstr ""
+
+#: src/main/help.c:403
 msgid "PID"
 msgstr ""
 
-#: src/main/help.c:401
+#: src/main/help.c:404
 msgid "update settings of process PID"
 msgstr ""
 
-#: src/main/help.c:406
+#: src/main/help.c:409
 msgid "save process ID in FILE"
 msgstr ""
 
-#: src/main/help.c:409
+#: src/main/help.c:412
 msgid "PID[:FD]"
 msgstr ""
 
-#: src/main/help.c:410
+#: src/main/help.c:413
 msgid "watch file FD opened by process PID"
 msgstr ""
 
-#: src/main/help.c:414
+#: src/main/help.c:417
 msgid "show this help and exit"
 msgstr "wyświetl te informacje z pomocą i wyjdź"
 
-#: src/main/help.c:417
+#: src/main/help.c:420
 msgid "show version information and exit"
 msgstr "wyświetl informacje o wersji i wyjdź"
 
-#: src/main/help.c:421
+#: src/main/help.c:424
 msgid "write debug logs to FILE"
 msgstr ""
 
-#: src/main/help.c:446
+#: src/main/help.c:449
 #, c-format
 msgid "Usage: %s [OPTION] [FILE]..."
 msgstr "Sposób użycia: %s [OPCJA] [PLIK]..."
 
-#: src/main/help.c:457
+#: src/main/help.c:460
 msgid ""
 "Concatenate FILE(s), or standard input, to standard output, with monitoring."
 msgstr ""
 "Łączenie PLIK(ów) lub wejścia standardowego, do wyjścia standardowego z "
 "monitoringiem."
 
-#: src/main/help.c:594
+#: src/main/help.c:597
 #, c-format
 msgid "Please report any bugs to: %s"
 msgstr "Proszę przesyłać zgłoszenia błędów do %s"
 
-#: src/main/main.c:71
+#: src/main/main.c:214
+msgid "(input)"
+msgstr ""
+
+#: src/main/main.c:299
 msgid "state allocation failed"
 msgstr ""
 
-#: src/main/options.c:138 src/pv/file.c:324
+#: src/main/options.c:140 src/pv/file.c:324
 msgid "failed to stat file"
 msgstr "nie udało się wykonać operacji stat na pliku"
 
-#: src/main/options.c:152
+#: src/main/options.c:154
 msgid "is a directory"
 msgstr ""
 
-#: src/main/options.c:181
+#: src/main/options.c:183
 msgid "failed to generate sysfs filename"
 msgstr ""
 
-#: src/main/options.c:203
+#: src/main/options.c:205
 msgid "failed to read sysfs size file"
 msgstr ""
 
-#: src/main/options.c:223
+#: src/main/options.c:225
 msgid "failed to open block device"
 msgstr ""
 
-#: src/main/options.c:233
+#: src/main/options.c:235
 msgid "failed to determine size of block device"
 msgstr ""
 
-#: src/main/options.c:336
+#: src/main/options.c:339
 msgid "option structure allocation failed"
 msgstr "nie udało się zaalokować struktur opcji"
 
-#: src/main/options.c:355
+#: src/main/options.c:358
 msgid "option structure argv allocation failed"
 msgstr "nie udało się zaalokować struktur opcji argv"
 
-#: src/main/options.c:417
+#: src/main/options.c:420
 msgid "integer argument expected"
 msgstr ""
 
-#: src/main/options.c:428
+#: src/main/options.c:431
 msgid "numeric argument expected"
 msgstr ""
 
-#: src/main/options.c:439
+#: src/main/options.c:442
 msgid "process ID or pid:fd pair expected"
 msgstr ""
 
-#: src/main/options.c:446
+#: src/main/options.c:449
 msgid "invalid process ID"
 msgstr ""
 
-#: src/main/options.c:655
+#: src/main/options.c:666
 #, c-format
 msgid "Try `%s --help' for more information."
 msgstr "Spróbuj `%s --help' by uzyskać więcej informacji"
 
-#: src/main/options.c:657
+#: src/main/options.c:668
 #, c-format
 msgid "Try `%s -h' for more information."
 msgstr "Spróbuj `%s -h' by uzyskać więcej informacji"
 
-#: src/main/options.c:688
+#: src/main/options.c:699
 msgid ""
 "cannot use line mode or transfer modifier options when watching file "
 "descriptors"
 msgstr ""
 
-#: src/main/options.c:697
+#: src/main/options.c:708
 msgid "cannot use cursor positioning when watching file descriptors"
 msgstr ""
 
-#: src/main/options.c:706
+#: src/main/options.c:717
 msgid "cannot use remote control when watching file descriptors"
 msgstr ""
 
-#: src/main/options.c:715
+#: src/main/options.c:726
 msgid "cannot transfer files when watching file descriptors"
 msgstr ""
 
-#: src/main/options.c:730
+#: src/main/options.c:741
 msgid "not available on systems without /proc/self/fdinfo"
 msgstr ""
 
@@ -381,45 +390,45 @@ msgstr ""
 msgid "failed to open terminal"
 msgstr "nie udało się otworzyć terminala"
 
-#: src/pv/display.c:216
+#: src/pv/display.c:230
 msgid "yzafpnum kMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:234
+#: src/pv/display.c:248
 msgid "yzafpnum KMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:661 src/pv/transfer.c:970
+#: src/pv/display.c:675 src/pv/transfer.c:970
 msgid "buffer allocation failed"
 msgstr "nie udało się zaalokować bufora"
 
-#: src/pv/display.c:790
+#: src/pv/display.c:804
 msgid "b"
 msgstr ""
 
-#: src/pv/display.c:793 src/pv/transfer.c:602
+#: src/pv/display.c:807 src/pv/transfer.c:602
 msgid "B"
 msgstr "B"
 
-#: src/pv/display.c:837 src/pv/display.c:852 src/pv/display.c:1071
-#: src/pv/loop.c:418
+#: src/pv/display.c:851 src/pv/display.c:866 src/pv/display.c:1085
+#: src/pv/loop.c:494
 msgid "b/s"
 msgstr ""
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
 msgid "/s"
 msgstr "/s"
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
-#: src/pv/loop.c:418
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
+#: src/pv/loop.c:494
 msgid "B/s"
 msgstr "B/s"
 
-#: src/pv/display.c:884 src/pv/display.c:888
+#: src/pv/display.c:898 src/pv/display.c:902
 msgid "ETA"
 msgstr "ETA"
 
-#: src/pv/display.c:954
+#: src/pv/display.c:968
 msgid "FIN"
 msgstr ""
 
@@ -452,15 +461,15 @@ msgstr ""
 msgid "(stdin)"
 msgstr ""
 
-#: src/pv/loop.c:417
+#: src/pv/loop.c:493
 msgid "rate min/avg/max/mdev"
 msgstr ""
 
-#: src/pv/loop.c:429
+#: src/pv/loop.c:505
 msgid "rate not measured"
 msgstr ""
 
-#: src/pv/loop.c:635 src/pv/loop.c:686 src/pv/loop.c:727 src/pv/watchpid.c:99
+#: src/pv/loop.c:711 src/pv/loop.c:762 src/pv/loop.c:803 src/pv/watchpid.c:99
 #: src/pv/watchpid.c:109 src/pv/watchpid.c:120 src/pv/watchpid.c:128
 #: src/pv/watchpid.c:165 src/pv/watchpid.c:184 src/pv/watchpid.c:192
 #: src/pv/watchpid.c:202 src/pv/watchpid.c:293 src/pv/watchpid.c:301
@@ -472,7 +481,7 @@ msgstr ""
 msgid "history structure allocation failed"
 msgstr ""
 
-#: src/pv/state.c:470 src/pv/state.c:481
+#: src/pv/state.c:501 src/pv/state.c:512
 msgid "file list allocation failed"
 msgstr ""
 
diff --git a/po/pt.po b/po/pt.po
index 6f0d2ee..ca2872b 100644
--- a/po/pt.po
+++ b/po/pt.po
@@ -6,7 +6,7 @@ msgid ""
 msgstr ""
 "Project-Id-Version: PACKAGE VERSION\n"
 "Report-Msgid-Bugs-To: pv@ivarch.com\n"
-"POT-Creation-Date: 2024-10-04 22:08+0100\n"
+"POT-Creation-Date: 2024-10-05 16:04+0100\n"
 "PO-Revision-Date: YEAR-MO-DA HO:MI+ZONE\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
@@ -155,7 +155,8 @@ msgstr "gera dados mesmo que a saída de erro seja redirecionada"
 msgid "use cursor positioning escape sequences"
 msgstr "utiliza caracteres de escape para posicionar o cursor"
 
-#: src/main/help.c:369 src/main/help.c:405 src/main/help.c:420
+#: src/main/help.c:369 src/main/help.c:399 src/main/help.c:408
+#: src/main/help.c:423
 msgid "FILE"
 msgstr ""
 
@@ -208,117 +209,125 @@ msgid "discard input instead of writing to output"
 msgstr ""
 
 #: src/main/help.c:400
+msgid "write all input to FILE before writing to output"
+msgstr ""
+
+#: src/main/help.c:403
 msgid "PID"
 msgstr ""
 
-#: src/main/help.c:401
+#: src/main/help.c:404
 msgid "update settings of process PID"
 msgstr "atualizar as configurações do processo PID"
 
-#: src/main/help.c:406
+#: src/main/help.c:409
 msgid "save process ID in FILE"
 msgstr "salvar ID do processo em FILE"
 
-#: src/main/help.c:409
+#: src/main/help.c:412
 msgid "PID[:FD]"
 msgstr ""
 
-#: src/main/help.c:410
+#: src/main/help.c:413
 msgid "watch file FD opened by process PID"
 msgstr "assistir arquivo FD aberto pelo processo PID"
 
-#: src/main/help.c:414
+#: src/main/help.c:417
 msgid "show this help and exit"
 msgstr "exibe esta tela de ajuda e termina"
 
-#: src/main/help.c:417
+#: src/main/help.c:420
 msgid "show version information and exit"
 msgstr "exibe a versão e termina"
 
-#: src/main/help.c:421
+#: src/main/help.c:424
 msgid "write debug logs to FILE"
 msgstr ""
 
-#: src/main/help.c:446
+#: src/main/help.c:449
 #, c-format
 msgid "Usage: %s [OPTION] [FILE]..."
 msgstr "Uso: %s [OPÇÕES] [ARQUIVOS]..."
 
-#: src/main/help.c:457
+#: src/main/help.c:460
 msgid ""
 "Concatenate FILE(s), or standard input, to standard output, with monitoring."
 msgstr ""
 "Concatena ARQUIVO(s) ou a entrada padrão e grava na saída padrão, com "
 "monitoramento."
 
-#: src/main/help.c:594
+#: src/main/help.c:597
 #, c-format
 msgid "Please report any bugs to: %s"
 msgstr "Por favor, reporte quaisquer defeitos para %s"
 
-#: src/main/main.c:71
+#: src/main/main.c:214
+msgid "(input)"
+msgstr ""
+
+#: src/main/main.c:299
 msgid "state allocation failed"
 msgstr "alocação de memória de status falhou"
 
-#: src/main/options.c:138 src/pv/file.c:324
+#: src/main/options.c:140 src/pv/file.c:324
 msgid "failed to stat file"
 msgstr "erro obtendo informações do arquivo"
 
-#: src/main/options.c:152
+#: src/main/options.c:154
 msgid "is a directory"
 msgstr ""
 
-#: src/main/options.c:181
+#: src/main/options.c:183
 msgid "failed to generate sysfs filename"
 msgstr ""
 
-#: src/main/options.c:203
+#: src/main/options.c:205
 msgid "failed to read sysfs size file"
 msgstr ""
 
-#: src/main/options.c:223
+#: src/main/options.c:225
 msgid "failed to open block device"
 msgstr ""
 
-#: src/main/options.c:233
+#: src/main/options.c:235
 msgid "failed to determine size of block device"
 msgstr ""
 
-#: src/main/options.c:336
+#: src/main/options.c:339
 msgid "option structure allocation failed"
 msgstr "erro na alocação da estrutura de opções"
 
-#: src/main/options.c:355
+#: src/main/options.c:358
 msgid "option structure argv allocation failed"
 msgstr "erro na alocação da estrutura de opções argv"
 
-#: src/main/options.c:417
+#: src/main/options.c:420
 msgid "integer argument expected"
 msgstr "argumento inteiro esperado"
 
-#: src/main/options.c:428
+#: src/main/options.c:431
 msgid "numeric argument expected"
 msgstr "argumento numérico esperado"
 
-#: src/main/options.c:439
+#: src/main/options.c:442
 msgid "process ID or pid:fd pair expected"
 msgstr "ID do processo ou par pid:fd esperado"
 
-#: src/main/options.c:446
+#: src/main/options.c:449
 msgid "invalid process ID"
 msgstr "ID de processo inválido"
 
-#: src/main/options.c:655
+#: src/main/options.c:666
 #, c-format
 msgid "Try `%s --help' for more information."
 msgstr "Tente `%s --help' para maiores informações."
 
-#: src/main/options.c:657
+#: src/main/options.c:668
 #, c-format
 msgid "Try `%s -h' for more information."
 msgstr "Tente `%s -h' para maiores informações."
 
-#: src/main/options.c:688
+#: src/main/options.c:699
 msgid ""
 "cannot use line mode or transfer modifier options when watching file "
 "descriptors"
@@ -326,21 +335,21 @@ msgstr ""
 "não pode usar o modo de linha ou opções de modificador de transferência ao "
 "assistir os descritores de arquivo"
 
-#: src/main/options.c:697
+#: src/main/options.c:708
 msgid "cannot use cursor positioning when watching file descriptors"
 msgstr ""
 "não pode usar o posicionamento do cursor ao observar os descritores de "
 "arquivo"
 
-#: src/main/options.c:706
+#: src/main/options.c:717
 msgid "cannot use remote control when watching file descriptors"
 msgstr "não pode usar o controle remoto ao assistir os descritores de arquivo"
 
-#: src/main/options.c:715
+#: src/main/options.c:726
 msgid "cannot transfer files when watching file descriptors"
 msgstr "não pode transferir arquivos ao assistir descritores de arquivo"
 
-#: src/main/options.c:730
+#: src/main/options.c:741
 msgid "not available on systems without /proc/self/fdinfo"
 msgstr "não disponível em sistemas sem /proc/self/fdinfo"
 
@@ -384,45 +393,45 @@ msgstr "tentativa de bloqueio falhou"
 msgid "failed to open terminal"
 msgstr "erro abrindo o terminal"
 
-#: src/pv/display.c:216
+#: src/pv/display.c:230
 msgid "yzafpnum kMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:234
+#: src/pv/display.c:248
 msgid "yzafpnum KMGTPEZY"
 msgstr ""
 
-#: src/pv/display.c:661 src/pv/transfer.c:970
+#: src/pv/display.c:675 src/pv/transfer.c:970
 msgid "buffer allocation failed"
 msgstr "erro alocando o buffer"
 
-#: src/pv/display.c:790
+#: src/pv/display.c:804
 msgid "b"
 msgstr ""
 
-#: src/pv/display.c:793 src/pv/transfer.c:602
+#: src/pv/display.c:807 src/pv/transfer.c:602
 msgid "B"
 msgstr ""
 
-#: src/pv/display.c:837 src/pv/display.c:852 src/pv/display.c:1071
-#: src/pv/loop.c:418
+#: src/pv/display.c:851 src/pv/display.c:866 src/pv/display.c:1085
+#: src/pv/loop.c:494
 msgid "b/s"
 msgstr ""
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
 msgid "/s"
 msgstr ""
 
-#: src/pv/display.c:841 src/pv/display.c:856 src/pv/display.c:1075
-#: src/pv/loop.c:418
+#: src/pv/display.c:855 src/pv/display.c:870 src/pv/display.c:1089
+#: src/pv/loop.c:494
 msgid "B/s"
 msgstr "B/s"
 
-#: src/pv/display.c:884 src/pv/display.c:888
+#: src/pv/display.c:898 src/pv/display.c:902
 msgid "ETA"
 msgstr "ETA"
 
-#: src/pv/display.c:954
+#: src/pv/display.c:968
 msgid "FIN"
 msgstr ""
 
@@ -454,15 +463,15 @@ msgstr ""
 msgid "(stdin)"
 msgstr ""
 
-#: src/pv/loop.c:417
+#: src/pv/loop.c:493
 msgid "rate min/avg/max/mdev"
 msgstr ""
 
-#: src/pv/loop.c:429
+#: src/pv/loop.c:505
 msgid "rate not measured"
 msgstr ""
 
-#: src/pv/loop.c:635 src/pv/loop.c:686 src/pv/loop.c:727 src/pv/watchpid.c:99
+#: src/pv/loop.c:711 src/pv/loop.c:762 src/pv/loop.c:803 src/pv/watchpid.c:99
 #: src/pv/watchpid.c:109 src/pv/watchpid.c:120 src/pv/watchpid.c:128
 #: src/pv/watchpid.c:165 src/pv/watchpid.c:184 src/pv/watchpid.c:192
 #: src/pv/watchpid.c:202 src/pv/watchpid.c:293 src/pv/watchpid.c:301
@@ -474,7 +483,7 @@ msgstr ""
 msgid "history structure allocation failed"
 msgstr ""
 
-#: src/pv/state.c:470 src/pv/state.c:481
+#: src/pv/state.c:501 src/pv/state.c:512
 msgid "file list allocation failed"
 msgstr ""
 
diff --git a/src/include/options.h b/src/include/options.h
index b2f5412..4d0c5bb 100644
--- a/src/include/options.h
+++ b/src/include/options.h
@@ -36,6 +36,7 @@ struct opts_s {
 	/*@keep@*/ /*@null@*/ char *name;    /* display name, if any */
 	/*@keep@*/ /*@null@*/ char *format;  /* output format, if any */
 	/*@keep@*/ /*@null@*/ char *pidfile; /* PID file, if any */
+	/*@keep@*/ /*@null@*/ char *store_and_forward_file; /* store and forward file, if any */
 	/*@keep@*/ /*@null@*/ const char **argv;   /* array of non-option arguments */
 	size_t lastwritten;            /* show N bytes last written */
 	off_t rate_limit;              /* rate limit, in bytes per second */
diff --git a/src/include/pv-internal.h b/src/include/pv-internal.h
index 865f630..693ad15 100644
--- a/src/include/pv-internal.h
+++ b/src/include/pv-internal.h
@@ -230,13 +230,13 @@ struct pvstate_s {
 		/* Keep track of progress over last intervals to compute current average rate. */
 		/*@null@*/ struct {	 /* state at previous intervals (circular buffer) */
 			long double elapsed_sec;	/* time since start of transfer */
-			off_t total_written;		/* amount transferred by that time */
+			off_t transferred;		/* amount transferred by that time */
 		} *history;
 		size_t history_len;		 /* total size of history array */
 		size_t history_first;		 /* index of oldest entry */
 		size_t history_last;		 /* index of newest entry */
 
-		off_t prev_total_written;	 /* total amount transferred when called last time */
+		off_t prev_transferred;		 /* total amount transferred when called last time */
 
 		int percentage;			 /* transfer percentage completion */
 	} calc;
@@ -290,7 +290,10 @@ struct pvstate_s {
 		ssize_t to_write;		 /* max to write this time around */
 		ssize_t written;		 /* bytes sent to stdout this time */
 
-		off_t total_written;		 /* total bytes or lines transferred */
+		size_t written_but_not_consumed; /* bytes in the output pipe, unread */
+
+		off_t total_written;		 /* total bytes or lines written */
+		off_t transferred;		 /* amount transferred (written - unconsumed) */
 
 		/*
 		 * While reading from a file descriptor we keep track of how
diff --git a/src/include/pv.h b/src/include/pv.h
index cfc9f6f..f468b9a 100644
--- a/src/include/pv.h
+++ b/src/include/pv.h
@@ -27,6 +27,7 @@ extern "C" {
  * Exit status bitmask values.
  */
 #define PV_ERROREXIT_REMOTE_OR_PID 1
+#define PV_ERROREXIT_SAF	   1	/* store and forward error */
 #define PV_ERROREXIT_ACCESS        2
 #define PV_ERROREXIT_OUROBOROS     4
 #define PV_ERROREXIT_TRANSITION    8
@@ -163,6 +164,11 @@ void pv_nanosleep(long long);
  */
 extern /*@null@*/ /*@only@*/ pvstate_t pv_state_alloc(const char *);
 
+/*
+ * Clear the calculated parts of a state structure.
+ */
+extern void pv_state_reset(pvstate_t state);
+
 /*
  * Set the formatting string, given a set of old-style formatting options.
  */
diff --git a/src/main/help.c b/src/main/help.c
index eda41ae..e0c8533 100644
--- a/src/main/help.c
+++ b/src/main/help.c
@@ -396,6 +396,9 @@ void display_help(void)
 		{ "-X", "--discard", NULL,
 		 N_("discard input instead of writing to output"),
 		 { 0, 0, 0, 0} },
+		{ "-U", "--store-and-forward", N_("FILE"),
+		 N_("write all input to FILE before writing to output"),
+		 { 0, 0, 0, 0} },
 #ifdef SA_SIGINFO
 		{ "-R", "--remote", N_("PID"),
 		 N_("update settings of process PID"),
diff --git a/src/main/main.c b/src/main/main.c
index f3034e5..46550aa 100644
--- a/src/main/main.c
+++ b/src/main/main.c
@@ -25,6 +25,233 @@ int pv_remote_set(opts_t, pvstate_t);
 void pv_remote_init(void);
 void pv_remote_fini(void);
 
+/*
+ * Write a PID file, returning nonzero on error.
+ */
+static int pv__write_pidfile(opts_t opts)
+{
+	char *pidfile_tmp_name;
+	size_t pidfile_tmp_bufsize;
+	int pidfile_tmp_fd;
+	FILE *pidfile_tmp_fptr;
+	mode_t prev_umask;
+
+	if (NULL == opts->pidfile)
+		return 0;
+
+	pidfile_tmp_bufsize = 16 + strlen(opts->pidfile);	/* flawfinder: ignore */
+	/*
+	 * flawfinder rationale: pidfile was supplied as an argument
+	 * so we have to assume it is \0 terminated.
+	 */
+	pidfile_tmp_name = malloc(pidfile_tmp_bufsize);
+	if (NULL == pidfile_tmp_name) {
+		fprintf(stderr, "%s: %s\n", opts->program_name, strerror(errno));
+		return PV_ERROREXIT_REMOTE_OR_PID;
+	}
+	memset(pidfile_tmp_name, 0, pidfile_tmp_bufsize);
+	(void) pv_snprintf(pidfile_tmp_name, pidfile_tmp_bufsize, "%s.XXXXXX", opts->pidfile);
+
+	/*@-type@ *//* splint doesn't like mode_t */
+	prev_umask = umask(0000);	    /* flawfinder: ignore */
+	(void) umask(prev_umask | 0133);    /* flawfinder: ignore */
+
+	/*@-unrecog@ *//* splint doesn't know mkstemp() */
+	pidfile_tmp_fd = mkstemp(pidfile_tmp_name);	/* flawfinder: ignore */
+	/*@+unrecog@ */
+	if (pidfile_tmp_fd < 0) {
+		fprintf(stderr, "%s: %s: %s\n", opts->program_name, pidfile_tmp_name, strerror(errno));
+		(void) umask(prev_umask);   /* flawfinder: ignore */
+		free(pidfile_tmp_name);
+		return PV_ERROREXIT_REMOTE_OR_PID;
+	}
+
+	(void) umask(prev_umask);	    /* flawfinder: ignore */
+
+	/*
+	 * flawfinder rationale (umask, mkstemp) - flawfinder
+	 * recommends setting the most restrictive umask possible
+	 * when calling mkstemp(), so this is what we have done.
+	 *
+	 * We get the original umask and OR it with 0133 to make
+	 * sure new files will be at least chmod 644.  Then we put
+	 * the umask back to what it was, after creating the
+	 * temporary file.
+	 */
+
+	/*@+type@ */
+
+	pidfile_tmp_fptr = fdopen(pidfile_tmp_fd, "w");
+	if (NULL == pidfile_tmp_fptr) {
+		fprintf(stderr, "%s: %s: %s\n", opts->program_name, pidfile_tmp_name, strerror(errno));
+		(void) close(pidfile_tmp_fd);
+		(void) remove(pidfile_tmp_name);
+		free(pidfile_tmp_name);
+		return PV_ERROREXIT_REMOTE_OR_PID;
+	}
+
+	fprintf(pidfile_tmp_fptr, "%d\n", getpid());
+	if (0 != fclose(pidfile_tmp_fptr)) {
+		fprintf(stderr, "%s: %s: %s\n", opts->program_name, opts->pidfile, strerror(errno));
+	}
+
+	if (rename(pidfile_tmp_name, opts->pidfile) < 0) {
+		fprintf(stderr, "%s: %s: %s\n", opts->program_name, opts->pidfile, strerror(errno));
+		(void) remove(pidfile_tmp_name);
+	}
+
+	free(pidfile_tmp_name);
+
+	return 0;
+}
+
+
+/*
+ * Set the output file, if applicable.  Returns nonzero on error.
+ */
+static int pv__set_output(pvstate_t state, opts_t opts, /*@null@ */ const char *output_file)
+{
+	int output_fd;
+
+	if ((NULL == state) || (NULL == opts))
+		return 0;
+
+	if (NULL == output_file || 0 == strcmp(output_file, "-")) {
+		pv_state_output_set(state, STDOUT_FILENO, "(stdout)");
+		return 0;
+	}
+
+	output_fd = open(output_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);	/* flawfinder: ignore */
+	/*
+	 * flawfinder rationale: the output filename has been
+	 * explicitly provided, and in many cases the operator will
+	 * want to write to device files and other special
+	 * destinations, so there is no sense-checking we can do to
+	 * make this safer.
+	 */
+	if (output_fd < 0) {
+		fprintf(stderr, "%s: %s: %s\n", opts->program_name, output_file, strerror(errno));
+		return PV_ERROREXIT_ACCESS;
+	}
+
+	pv_state_output_set(state, output_fd, output_file);
+	return 0;
+}
+
+
+/*
+ * Run in store-and-forward mode: run the main loop once with the output
+ * forced to the store-and-forward file (taking care of creation and removal
+ * of a temporary file if "-" was specified); then run the main loop again
+ * with the input file list forced to be just the store-and-forward file. 
+ * Returns nonzero on error.
+ */
+static int pv__store_and_forward(pvstate_t state, opts_t opts, bool can_have_eta)
+{
+	char tmp_filename[4096];	 /* flawfinder: ignore */
+	bool use_temporary_file;
+	char *real_store_and_forward_file;
+	int retcode;
+
+	/* flawfinder: zeroed with memset and bounded by pv_snprintf. */
+
+	if ((NULL == state) || (NULL == opts) || (NULL == opts->store_and_forward_file))
+		return 0;
+
+	memset(tmp_filename, 0, sizeof(tmp_filename));
+
+	use_temporary_file = false;
+	if (0 == strcmp(opts->store_and_forward_file, "-"))
+		use_temporary_file = true;
+
+	/*
+	 * Create a temporary file if the specified file was "-".
+	 */
+	if (use_temporary_file) {
+		char *tmpdir;
+		int tmp_fd;
+
+		tmpdir = (char *) getenv("TMPDIR");	/* flawfinder: ignore */
+		if ((NULL == tmpdir) || ('\0' == tmpdir[0]))
+			tmpdir = (char *) getenv("TMP");	/* flawfinder: ignore */
+		if ((NULL == tmpdir) || ('\0' == tmpdir[0]))
+			tmpdir = "/tmp";
+
+		/*
+		 * flawfinder rationale: null and zero-size values of $TMPDIR and
+		 * $TMP are rejected, and the destination buffer is bounded.
+		 */
+
+		(void) pv_snprintf(tmp_filename, sizeof(tmp_filename), "%s/pv.XXXXXX", tmpdir);
+		/*@-unrecog@ *//* splint doesn't know mkstemp() */
+		tmp_fd = mkstemp(tmp_filename);	/* flawfinder: ignore */
+		/*@+unrecog@ */
+		if (tmp_fd < 0) {
+			fprintf(stderr, "%s: %s: %s\n", opts->program_name, tmp_filename, strerror(errno));
+			return PV_ERROREXIT_SAF;
+		}
+		(void) close(tmp_fd);
+	}
+
+	/*
+	 * Real store-and-forward file: either the one we were given, or the
+	 * temporary file we created if we were given "-".
+	 */
+	real_store_and_forward_file = use_temporary_file ? tmp_filename : opts->store_and_forward_file;
+
+	/*
+	 * First, set the output file to the store-and-forward file.
+	 */
+	debug("%s: %s", "setting output to store-and-forward file", real_store_and_forward_file);
+	retcode = pv__set_output(state, opts, real_store_and_forward_file);
+	if (0 != retcode)
+		goto end_store_and_forward;
+
+	/* Reset the formatting to set the displayed name to "(input)". */
+	/*@-mustfreefresh@ */
+	pv_state_set_format(state, opts->progress, opts->timer, can_have_eta ? opts->eta : false,
+			    can_have_eta ? opts->fineta : false, opts->rate, opts->average_rate,
+			    opts->bytes, opts->bufpercent, opts->lastwritten, _("(input)"));
+	/*@+mustfreefresh@ *//* see below about gettext _() calls. */
+
+	/* Run the main loop as normal. */
+	debug("%s", "running store-and-forward receiver");
+	retcode = pv_main_loop(state);
+	if (0 != retcode)
+		goto end_store_and_forward;
+
+	/* Set the output file back to what it originally was. */
+	debug("%s: %s", "setting output to original value", NULL == opts->output ? "(null)" : opts->output);
+	retcode = pv__set_output(state, opts, opts->output);
+	if (0 != retcode)
+		goto end_store_and_forward;
+
+	/* Replace the list of input files with the store-and-forward file. */
+	debug("%s", "resetting input file list");
+	pv_state_inputfiles(state, 1, (const char **) &real_store_and_forward_file);
+
+	/* Recalculate the input size. */
+	pv_state_size_set(state, pv_calc_total_size(state));
+
+	/* Reset the format, since we might have been asked to show ETA. */
+	pv_state_set_format(state, opts->progress, opts->timer, opts->eta,
+			    opts->fineta, opts->rate, opts->average_rate,
+			    opts->bytes, opts->bufpercent, opts->lastwritten, opts->name);
+
+	/* Reset calculated values in the state. */
+	pv_state_reset(state);
+
+	/* Run the main loop again. */
+	debug("%s", "running store-and-forward transmitter");
+	retcode = pv_main_loop(state);
+
+      end_store_and_forward:
+	if (use_temporary_file)
+		(void) remove(tmp_filename);
+
+	return retcode;
+}
+
 
 /*
  * Process command-line arguments and set option flags, then call functions
@@ -35,6 +262,7 @@ int main(int argc, char **argv)
 	/*@only@ */ opts_t opts = NULL;
 	/*@only@ */ pvstate_t state = NULL;
 	int retcode = 0;
+	bool can_have_eta = true;
 
 #ifdef ENABLE_NLS
 	/* Initialise language translation. */
@@ -96,80 +324,13 @@ int main(int argc, char **argv)
 	 * Write a PID file if -P was specified.
 	 */
 	if (opts->pidfile != NULL) {
-		char *pidfile_tmp_name;
-		size_t pidfile_tmp_bufsize;
-		int pidfile_tmp_fd;
-		FILE *pidfile_tmp_fptr;
-		mode_t prev_umask;
-
-		pidfile_tmp_bufsize = 16 + strlen(opts->pidfile);	/* flawfinder: ignore */
-		/*
-		 * flawfinder rationale: pidfile was supplied as an argument
-		 * so we have to assume it is \0 terminated.
-		 */
-		pidfile_tmp_name = malloc(pidfile_tmp_bufsize);
-		if (NULL == pidfile_tmp_name) {
-			fprintf(stderr, "%s: %s\n", opts->program_name, strerror(errno));
+		int pidfile_rc;
+		pidfile_rc = pv__write_pidfile(opts);
+		if (0 != pidfile_rc) {
 			pv_state_free(state);
 			opts_free(opts);
-			return PV_ERROREXIT_REMOTE_OR_PID;
+			return pidfile_rc;
 		}
-		memset(pidfile_tmp_name, 0, pidfile_tmp_bufsize);
-		(void) pv_snprintf(pidfile_tmp_name, pidfile_tmp_bufsize, "%s.XXXXXX", opts->pidfile);
-
-		/*@-type@ *//* splint doesn't like mode_t */
-		prev_umask = umask(0000);   /* flawfinder: ignore */
-		(void) umask(prev_umask | 0133);	/* flawfinder: ignore */
-
-		/*@-unrecog@ *//* splint doesn't know mkstemp() */
-		pidfile_tmp_fd = mkstemp(pidfile_tmp_name);	/* flawfinder: ignore */
-		/*@+unrecog@ */
-		if (pidfile_tmp_fd < 0) {
-			fprintf(stderr, "%s: %s: %s\n", opts->program_name, pidfile_tmp_name, strerror(errno));
-			(void) umask(prev_umask);	/* flawfinder: ignore */
-			free(pidfile_tmp_name);
-			pv_state_free(state);
-			opts_free(opts);
-			return PV_ERROREXIT_REMOTE_OR_PID;
-		}
-
-		(void) umask(prev_umask);   /* flawfinder: ignore */
-
-		/*
-		 * flawfinder rationale (umask, mkstemp) - flawfinder
-		 * recommends setting the most restrictive umask possible
-		 * when calling mkstemp(), so this is what we have done.
-		 *
-		 * We get the original umask and OR it with 0133 to make
-		 * sure new files will be at least chmod 644.  Then we put
-		 * the umask back to what it was, after creating the
-		 * temporary file.
-		 */
-
-		/*@+type@ */
-
-		pidfile_tmp_fptr = fdopen(pidfile_tmp_fd, "w");
-		if (NULL == pidfile_tmp_fptr) {
-			fprintf(stderr, "%s: %s: %s\n", opts->program_name, pidfile_tmp_name, strerror(errno));
-			(void) close(pidfile_tmp_fd);
-			(void) remove(pidfile_tmp_name);
-			free(pidfile_tmp_name);
-			pv_state_free(state);
-			opts_free(opts);
-			return PV_ERROREXIT_REMOTE_OR_PID;
-		}
-
-		fprintf(pidfile_tmp_fptr, "%d\n", getpid());
-		if (0 != fclose(pidfile_tmp_fptr)) {
-			fprintf(stderr, "%s: %s: %s\n", opts->program_name, opts->pidfile, strerror(errno));
-		}
-
-		if (rename(pidfile_tmp_name, opts->pidfile) < 0) {
-			fprintf(stderr, "%s: %s: %s\n", opts->program_name, opts->pidfile, strerror(errno));
-			(void) remove(pidfile_tmp_name);
-		}
-
-		free(pidfile_tmp_name);
 	}
 
 	/*
@@ -246,24 +407,11 @@ int main(int argc, char **argv)
 	 * calculation looks at the output file if the input size can't be
 	 * calculated (issue #91).
 	 */
-	if (NULL == opts->output || 0 == strcmp(opts->output, "-")) {
-		pv_state_output_set(state, STDOUT_FILENO, "(stdout)");
-	} else {
-		int fd = open(opts->output, O_WRONLY | O_CREAT | O_TRUNC, 0600);	/* flawfinder: ignore */
-		/*
-		 * flawfinder rationale: the output filename has been
-		 * explicitly provided, and in many cases the operator will
-		 * want to write to device files and other special
-		 * destinations, so there is no sense-checking we can do to
-		 * make this safer.
-		 */
-		if (fd < 0) {
-			fprintf(stderr, "%s: %s: %s\n", opts->program_name, opts->output, strerror(errno));
-			pv_state_free(state);
-			opts_free(opts);
-			return PV_ERROREXIT_ACCESS;
-		}
-		pv_state_output_set(state, fd, opts->output);
+	retcode = pv__set_output(state, opts, opts->output);
+	if (0 != retcode) {
+		pv_state_free(state);
+		opts_free(opts);
+		return retcode;
 	}
 
 	/*
@@ -290,7 +438,7 @@ int main(int argc, char **argv)
 		 * If the size is unknown, we cannot have an ETA.
 		 */
 		if (opts->size < 1) {
-			opts->eta = false;
+			can_have_eta = false;
 			debug("%s", "size unknown - ETA disabled");
 		}
 	}
@@ -330,19 +478,24 @@ int main(int argc, char **argv)
 	pv_state_watch_fd_set(state, opts->watch_fd);
 	pv_state_average_rate_window_set(state, opts->average_rate_window);
 
-	pv_state_set_format(state, opts->progress, opts->timer, opts->eta,
-			    opts->fineta, opts->rate, opts->average_rate,
+	pv_state_set_format(state, opts->progress, opts->timer, can_have_eta ? opts->eta : false,
+			    can_have_eta ? opts->fineta : false, opts->rate, opts->average_rate,
 			    opts->bytes, opts->bufpercent, opts->lastwritten, opts->name);
 
 	/* Initialise the signal handling. */
 	pv_sig_init(state);
 
 	/* Run the appropriate main loop. */
-	if (0 == opts->watch_pid) {
+	if (0 == opts->watch_pid && NULL == opts->store_and_forward_file) {
 		/* Normal "transfer data" mode. */
 		pv_remote_init();
 		retcode = pv_main_loop(state);
 		pv_remote_fini();
+	} else if (0 == opts->watch_pid && NULL != opts->store_and_forward_file) {
+		/* Store-and-forward transfer mode. */
+		pv_remote_init();
+		retcode = pv__store_and_forward(state, opts, can_have_eta);
+		pv_remote_fini();
 	} else if (0 != opts->watch_pid && -1 == opts->watch_fd) {
 		/* "Watch all file descriptors of another process" mode. */
 		retcode = pv_watchpid_loop(state);
diff --git a/src/main/options.c b/src/main/options.c
index c54c9bb..f6bd831 100644
--- a/src/main/options.c
+++ b/src/main/options.c
@@ -55,6 +55,8 @@ void opts_free( /*@only@ */ opts_t opts)
 		free(opts->pidfile);
 	if (NULL != opts->output)
 		free(opts->output);
+	if (NULL != opts->store_and_forward_file)
+		free(opts->store_and_forward_file);
 	if (NULL != opts->argv)
 		free(opts->argv);
 	/*@+keeptrans@ */
@@ -301,6 +303,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 		{ "sync", 0, NULL, (int) 'Y' },
 		{ "direct-io", 0, NULL, (int) 'K' },
 		{ "discard", 0, NULL, (int) 'X' },
+		{ "store-and-forward", 1, NULL, (int) 'U' },
 		{ "remote", 1, NULL, (int) 'R' },
 		{ "pidfile", 1, NULL, (int) 'P' },
 		{ "watchfd", 1, NULL, (int) 'd' },
@@ -314,7 +317,7 @@ opts_t opts_parse(unsigned int argc, char **argv)
 	/*@+nullassign@ */
 	int option_index = 0;
 #endif				/* HAVE_GETOPT_LONG */
-	char *short_options = "hVpteIrab8kTA:fvnqcWD:s:gl0i:w:H:N:F:L:B:CEZ:SYKXR:P:d:m:o:"
+	char *short_options = "hVpteIrab8kTA:fvnqcWD:s:gl0i:w:H:N:F:L:B:CEZ:SYKXU:R:P:d:m:o:"
 #ifdef ENABLE_DEBUGGING
 	    "!:"
 #endif
@@ -605,6 +608,14 @@ opts_t opts_parse(unsigned int argc, char **argv)
 			opts->discard_input = true;
 			opts->no_splice = true;
 			break;
+		case 'U':
+			opts->store_and_forward_file = pv_strdup(optarg);
+			if (NULL == opts->store_and_forward_file) {
+				fprintf(stderr, "%s: -U: %s\n", opts->program_name, strerror(errno));
+				opts_free(opts);
+				return NULL;
+			}
+			break;
 		case 'R':
 			opts->remote = pv_getnum_count(optarg, false);
 			break;
diff --git a/src/pv/calc.c b/src/pv/calc.c
index 5272a25..25ebe0c 100644
--- a/src/pv/calc.c
+++ b/src/pv/calc.c
@@ -51,12 +51,12 @@ static void pv__update_average_rate_history(pvstate_t state, long double rate)
 	}
 
 	state->calc.history[last].elapsed_sec = state->transfer.elapsed_seconds;
-	state->calc.history[last].total_written = state->transfer.total_written;
+	state->calc.history[last].transferred = state->transfer.transferred;
 
 	if (first == last) {
 		state->calc.current_avg_rate = rate;
 	} else {
-		off_t bytes = (state->calc.history[last].total_written - state->calc.history[first].total_written);
+		off_t bytes = (state->calc.history[last].transferred - state->calc.history[first].transferred);
 		long double sec = (state->calc.history[last].elapsed_sec - state->calc.history[first].elapsed_sec);
 		state->calc.current_avg_rate = (long double) bytes / sec;
 	}
@@ -85,9 +85,9 @@ void pv_calculate_transfer_rate(pvstate_t state, bool final)
 		return;
 
 	bytes_since_last = 0;
-	if (state->transfer.total_written >= 0) {
-		bytes_since_last = state->transfer.total_written - state->calc.prev_total_written;
-		state->calc.prev_total_written = state->transfer.total_written;
+	if (state->transfer.transferred >= 0) {
+		bytes_since_last = state->transfer.transferred - state->calc.prev_transferred;
+		state->calc.prev_transferred = state->transfer.transferred;
 	}
 
 	/*
@@ -138,7 +138,7 @@ void pv_calculate_transfer_rate(pvstate_t state, bool final)
 		if (state->transfer.elapsed_seconds < 0.000001)
 			state->transfer.elapsed_seconds = 0.000001;
 		average_rate =
-		    (((long double) state->transfer.total_written) -
+		    (((long double) (state->transfer.transferred)) -
 		     ((long double) state->display.initial_offset)) / (long double) (state->transfer.elapsed_seconds);
 		transfer_rate = average_rate;
 	}
@@ -160,7 +160,7 @@ void pv_calculate_transfer_rate(pvstate_t state, bool final)
 		if (state->calc.percentage > 199)
 			state->calc.percentage = 0;
 	} else {
-		state->calc.percentage = pv_percentage(state->transfer.total_written, state->control.size);
+		state->calc.percentage = pv_percentage(state->transfer.transferred, state->control.size);
 	}
 
 	/* Ensure the percentage is never negative or huge. */
diff --git a/src/pv/display.c b/src/pv/display.c
index 8e4fc2b..7fcf595 100644
--- a/src/pv/display.c
+++ b/src/pv/display.c
@@ -119,14 +119,28 @@ void pv_write_retry(int fd, const char *buf, size_t count)
 
 
 /*
- * Write the given buffer to the terminal with pv_write_retry(), unless
+ * Write the given buffer to the terminal, like pv_write_retry(), unless
  * stderr is suspended.
  */
 void pv_tty_write(pvstate_t state, const char *buf, size_t count)
 {
-	if (1 == state->flag.suspend_stderr)
-		return;
-	pv_write_retry(STDERR_FILENO, buf, count);
+	while (0 == state->flag.suspend_stderr && count > 0) {
+		ssize_t nwritten;
+
+		nwritten = write(STDERR_FILENO, buf, count);
+
+		if (nwritten < 0) {
+			if ((EINTR == errno) || (EAGAIN == errno)) {
+				continue;
+			}
+			return;
+		}
+		if (nwritten < 1)
+			return;
+
+		count -= nwritten;
+		buf += nwritten;
+	}
 }
 
 
@@ -706,7 +720,7 @@ bool pv_format(pvstate_t state, bool final)
 		if (state->display.component[PV_COMPONENT_BYTES].required) {
 			(void) pv_snprintf(msg_bytes, sizeof(msg_bytes),
 					   "%s%lld", first_item ? "" : " ",
-					   (long long) ((state->control.bits ? 8 : 1) * state->transfer.total_written));
+					   (long long) ((state->control.bits ? 8 : 1) * state->transfer.transferred));
 			first_item = false;
 			show_percentage = false;
 		}
@@ -787,10 +801,10 @@ bool pv_format(pvstate_t state, bool final)
 			/*@-mustfreefresh @ */
 			if (state->control.bits && !state->control.linemode) {
 				pv__sizestr(component_content, component_buf_size, "%s",
-					    (long double) (state->transfer.total_written * 8), "", _("b"), count_type);
+					    (long double) (state->transfer.transferred * 8), "", _("b"), count_type);
 			} else {
 				pv__sizestr(component_content, component_buf_size, "%s",
-					    (long double) (state->transfer.total_written), "", _("B"), count_type);
+					    (long double) (state->transfer.transferred), "", _("B"), count_type);
 			}
 			/*@+mustfreefresh @ */
 			/* splint: we trust gettext() not to really leak memory. */
@@ -862,7 +876,7 @@ bool pv_format(pvstate_t state, bool final)
 		case PV_COMPONENT_ETA:
 			/* Estimated time remaining until completion - if size is known. */
 			eta =
-			    pv__seconds_remaining((state->transfer.total_written - state->display.initial_offset),
+			    pv__seconds_remaining((state->transfer.transferred - state->display.initial_offset),
 						  state->control.size - state->display.initial_offset,
 						  state->calc.current_avg_rate);
 
@@ -917,7 +931,7 @@ bool pv_format(pvstate_t state, bool final)
 			 */
 
 			eta =
-			    pv__seconds_remaining(state->transfer.total_written - state->display.initial_offset,
+			    pv__seconds_remaining(state->transfer.transferred - state->display.initial_offset,
 						  state->control.size - state->display.initial_offset,
 						  state->calc.current_avg_rate);
 
diff --git a/src/pv/loop.c b/src/pv/loop.c
index eb69cd5..1949ab8 100644
--- a/src/pv/loop.c
+++ b/src/pv/loop.c
@@ -68,6 +68,7 @@ int pv_main_loop(pvstate_t state)
 	struct timespec init_time, next_remotecheck, transfer_elapsed;
 	int input_fd, output_fd;
 	unsigned int file_idx;
+	bool output_is_pipe;
 
 	/*
 	 * "written" is ALWAYS bytes written by the last transfer.
@@ -88,6 +89,35 @@ int pv_main_loop(pvstate_t state)
 	if (output_fd < 0)
 		output_fd = STDOUT_FILENO;
 
+	/* Determine whether the output is a pipe. */
+	output_is_pipe = false;
+	{
+		struct stat sb;
+		memset(&sb, 0, sizeof(sb));
+		if (0 == fstat(output_fd, &sb)) {
+			/*@-type@*/
+			if ((sb.st_mode & S_IFMT) == S_IFIFO) {
+				output_is_pipe = true;
+				debug("%s", "output is a pipe");
+			}
+			/*@+type@*/ /* splint says st_mode is __mode_t, not mode_t */
+		} else {
+			debug("%s(%d): %s", "fstat", output_fd, strerror(errno));
+		}
+	}
+
+	/*
+	 * Note that we could reduce the size of the output pipe buffer like
+	 * this, to avoid the case where we write a load of data and it just
+	 * goes into the buffer so we think we're done, but the consumer
+	 * takes ages to process it:
+	 *
+	 *   fcntl(output_fd, F_SETPIPE_SZ, 4096);
+	 *
+	 * If we can peek at how much has been consumed by the other end, we
+	 * don't need to.
+	 */
+
 	pv_crs_init(state);
 
 	eof_in = false;
@@ -95,6 +125,7 @@ int pv_main_loop(pvstate_t state)
 	state->transfer.total_written = 0;
 	lineswritten = 0;
 	state->display.initial_offset = 0;
+	state->transfer.written_but_not_consumed = 0;
 
 	memset(&cur_time, 0, sizeof(cur_time));
 	memset(&start_time, 0, sizeof(start_time));
@@ -147,8 +178,7 @@ int pv_main_loop(pvstate_t state)
 	/*
 	 * Set or clear O_DIRECT on the output.
 	 */
-	if (0 !=
-	    fcntl(output_fd, F_SETFL, (state->control.direct_io ? O_DIRECT : 0) | fcntl(output_fd, F_GETFL))) {
+	if (0 != fcntl(output_fd, F_SETFL, (state->control.direct_io ? O_DIRECT : 0) | fcntl(output_fd, F_GETFL))) {
 		debug("%s: %s", "fcntl", strerror(errno));
 	}
 	state->control.direct_io_changed = false;
@@ -176,6 +206,11 @@ int pv_main_loop(pvstate_t state)
 	if (0 == state->control.target_buffer_size)
 		state->control.target_buffer_size = BUFFER_SIZE;
 
+	/*
+	 * Repeat until eof_in is true, eof_out is true, and final_update is
+	 * true.
+	 */
+
 	while ((!(eof_in && eof_out)) || (!final_update)) {
 
 		cansend = 0;
@@ -249,6 +284,36 @@ int pv_main_loop(pvstate_t state)
 				target -= written;
 		}
 
+#ifdef FIONREAD
+		/*
+		 * If writing to a pipe, look at how much is sitting in the
+		 * pipe buffer waiting for the receiver to read.
+		 */
+		if (output_is_pipe) {
+			int nbytes;
+			nbytes = 0;
+			if (0 == ioctl(output_fd, FIONREAD, &nbytes)) {
+				if (nbytes >= 0) {
+					if (((size_t) nbytes) != state->transfer.written_but_not_consumed)
+						debug("%s: %d", "written_but_not_consumed is now", nbytes);
+					state->transfer.written_but_not_consumed = (size_t) nbytes;
+				} else {
+					debug("%s: %d", "FIONREAD gave a negative byte count", nbytes);
+					state->transfer.written_but_not_consumed = 0;
+				}
+			} else {
+				debug("%s(%d,%s): %s", "ioctl", output_fd, "FIONREAD", strerror(errno));
+				state->transfer.written_but_not_consumed = 0;
+			}
+		}
+#endif
+
+		state->transfer.transferred = state->transfer.total_written;
+		/* TODO: work out what to do in line mode. */
+		if (output_is_pipe && !state->control.linemode) {
+			state->transfer.transferred -= state->transfer.written_but_not_consumed;
+		}
+
 		/*
 		 * EOF, and files remain - advance to the next file.
 		 */
@@ -268,8 +333,12 @@ int pv_main_loop(pvstate_t state)
 		/* Now check the current time. */
 		pv_elapsedtime_read(&cur_time);
 
-		/* If full EOF, final update, and force a display updaate. */
-		if (eof_in && eof_out) {
+		/*
+		 * If we've read everything and written everything, and the
+		 * output pipe buffer is empty, then set the final update
+		 * flag, and force a display update.
+		 */
+		if (eof_in && eof_out && 0 == state->transfer.written_but_not_consumed) {
 			final_update = true;
 			if ((state->display.display_visible)
 			    || (state->control.delay_start < 0.001)) {
diff --git a/src/pv/state.c b/src/pv/state.c
index 3938037..3d202d8 100644
--- a/src/pv/state.c
+++ b/src/pv/state.c
@@ -46,6 +46,58 @@ static void pv_alloc_history(pvstate_t state)
 	state->calc.history[0].elapsed_sec = 0.0;	/* to be safe, memset() not recommended for doubles */
 }
 
+
+/*
+ * Clear the calculated parts of a state structure.
+ */
+void pv_state_reset(pvstate_t state)
+{
+	if (NULL == state)
+		return;
+
+	state->flag.reparse_display = 1;
+	state->status.current_input_file = -1;
+
+	state->display.initial_offset = 0;
+	state->display.display_visible = false;
+
+	/*
+	 * Explicitly set important floating point values to 0, as memset()
+	 * is not recommended for this.
+	 */
+	state->calc.transfer_rate = 0.0;
+	state->calc.average_rate = 0.0;
+	state->calc.prev_elapsed_sec = 0.0;
+	state->calc.prev_rate = 0.0;
+	state->calc.prev_trans = 0.0;
+	state->calc.current_avg_rate = 0.0;
+	state->calc.rate_min = 0.0;
+	state->calc.rate_max = 0.0;
+	state->calc.rate_sum = 0.0;
+	state->calc.ratesquared_sum = 0.0;
+	state->calc.measurements_taken = 0;
+	state->calc.prev_transferred = 0;
+	state->calc.percentage = 0;
+	state->calc.history_first = state->calc.history_last = 0;
+	if (NULL != state->calc.history) {
+		state->calc.history[0].elapsed_sec = 0.0;
+	}
+
+	state->transfer.elapsed_seconds = 0.0;
+	state->transfer.read_position = 0;
+	state->transfer.write_position = 0;
+	state->transfer.to_write = 0;
+	state->transfer.written = 0;
+	state->transfer.total_written = 0;
+	state->transfer.written_but_not_consumed = 0;
+	state->transfer.read_errors_in_a_row = 0;
+	state->transfer.last_read_skip_fd = 0;
+#ifdef HAVE_SPLICE
+	state->transfer.splice_failed_fd = -1;
+#endif				/* HAVE_SPLICE */
+}
+
+
 /*
  * Create a new state structure, and return it, or 0 (NULL) on error.
  */
@@ -78,28 +130,7 @@ pvstate_t pv_state_alloc(const char *program_name)
 #endif				/* HAVE_IPC */
 	state->cursor.lock_fd = -1;
 
-	state->flag.reparse_display = 1;
-	state->status.current_input_file = -1;
-#ifdef HAVE_SPLICE
-	state->transfer.splice_failed_fd = -1;
-#endif				/* HAVE_SPLICE */
-	state->display.display_visible = false;
-
-	/*
-	 * Explicitly set important floating point values to 0, as memset()
-	 * is not recommended for this.
-	 */
-	state->calc.transfer_rate = 0.0;
-	state->calc.average_rate = 0.0;
-	state->calc.prev_elapsed_sec = 0.0;
-	state->calc.prev_rate = 0.0;
-	state->calc.prev_trans = 0.0;
-	state->calc.current_avg_rate = 0.0;
-	state->calc.rate_min = 0.0;
-	state->calc.rate_max = 0.0;
-	state->calc.rate_sum = 0.0;
-	state->calc.ratesquared_sum = 0.0;
-	state->transfer.elapsed_seconds = 0.0;
+	pv_state_reset(state);
 
 	/*
 	 * Get the current working directory, if possible, as a base for