Correct issues #34, #86, #87 - progress output stopping when writing output data blocks - by adding a SIGALRM handler, since ignoring the signal prevents it from interrupting writes; and use setitimer() where available, instead of alarm(), to provide sufficient granularity to handle the case where the --interval is not a whole number of seconds.

src/include/config.h.in

@@ -100,6 +100,9 @@
 /* Define to 1 if you have the `select' function. */
 #undef HAVE_SELECT
 
+/* Define to 1 if you have the `setitimer' function. */
+#undef HAVE_SETITIMER
+
 /* Define to 1 if you have the `setlocale' function. */
 #undef HAVE_SETLOCALE
 

src/include/pv-internal.h

@@ -157,6 +157,7 @@ struct pvstate_s {
 #ifdef SA_SIGINFO
 		struct sigaction old_sigusr2;
 #endif
+		struct sigaction old_sigalrm;
 	} signal;
 
 	/*******************