Add a "--gauge" option which alters the progress bar to show the current rate as a percentage of the max rate seen, if the size is unknown (#46).

docs/NEWS.md

@@ -2,6 +2,7 @@
 
  * 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))
  * i18n: complete set of German translations supplied by Hartmut Goebel ([#98](https://codeberg.org/a-j-wood/pv/pulls/98))
  * fix: resume stopped pipelines when running in the background (part of [#56](https://codeberg.org/a-j-wood/pv/issues/56))
  * fix: prefix completion time ("`--fineta`") with *FIN* rather than *ETA* ([#43](https://codeberg.org/a-j-wood/pv/issues/43))

docs/pv.1

@@ -118,7 +118,10 @@ unreadable, and no size was explicitly given (with the
 .B \-s
 modifier), the progress bar cannot indicate how close to completion the
 transfer is, so it will just move left and right to indicate that data is
-moving.
+moving - or, with
+.BR \-\-gauge ,
+the bar will indicate the current rate as a percentage of the maximum rate
+seen so far.
 .TP
 .B \-t, \-\-timer
 Turn the timer on.  This will display the total elapsed time that
@@ -289,6 +292,11 @@ has no effect if used with
 to watch all file descriptors of a process, but will work with
 .BR "-d PID:FD" .
 .TP
+.B \-g, \-\-gauge
+If the progress bar is shown but the size is not known, then instead of
+moving the bar left and right to show progress, show the current transfer
+rate as a percentage of the maximum rate seen so far.
+.TP
 .B \-l, \-\-line\-mode
 Instead of counting bytes, count lines (newline characters). The progress
 bar will only move when a new line is found, and the value passed to the
@@ -635,6 +643,14 @@ average rate, and current rate.
 Show a progress bar, elapsed time, estimated completion time, line counter,
 and average rate, counting lines instead of bytes.
 .TP
+.B pv -btrpg
+Show the amount transferred, elapsed time, current rate, and a gauge showing
+the current rate as a percentage of the maximum rate seen - useful in a
+pipeline where the total size is unknown.  (If the size
+.I is
+known, these options will show the percentage completion instead of the rate
+gauge).
+.TP
 .B pv -t
 Show only the elapsed time - useful as a simple timer, e.g.
 .BR "sleep 10m | pv -t" .

docs/pv.1.md

@@ -80,7 +80,8 @@ display types that are explicitly switched on will be shown.
     unreadable, and no size was explicitly given (with the **-s**
     modifier), the progress bar cannot indicate how close to completion
     the transfer is, so it will just move left and right to indicate
-    that data is moving.
+    that data is moving - or, with **\--gauge**, the bar will indicate
+    the current rate as a percentage of the maximum rate seen so far.
 
 **-t, \--timer**
 
@@ -207,6 +208,12 @@ display types that are explicitly switched on will be shown.
     watch all file descriptors of a process, but will work with **-d
     PID:FD**.
 
+**-g, \--gauge**
+
+:   If the progress bar is shown but the size is not known, then instead
+    of moving the bar left and right to show progress, show the current
+    transfer rate as a percentage of the maximum rate seen so far.
+
 **-l, \--line-mode**
 
 :   Instead of counting bytes, count lines (newline characters). The
@@ -474,6 +481,14 @@ Some suggested common switch combinations:
 :   Show a progress bar, elapsed time, estimated completion time, line
     counter, and average rate, counting lines instead of bytes.
 
+**pv -btrpg**
+
+:   Show the amount transferred, elapsed time, current rate, and a gauge
+    showing the current rate as a percentage of the maximum rate seen -
+    useful in a pipeline where the total size is unknown. (If the size
+    *is* known, these options will show the percentage completion
+    instead of the rate gauge).
+
 **pv -t**
 
 :   Show only the elapsed time - useful as a simple timer, e.g. **sleep