>Number:         27213
>Category:       bin
>Synopsis:       pax doesn't honour SIGPIPE when listing
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    bin-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Sun Oct 10 20:23:00 UTC 2004
>Closed-Date:
>Last-Modified:
>Originator:     Greg A. Woods
>Release:        NetBSD-current
>Organization:
Planix, Inc.; Toronto, Ontario; Canada
>Environment:
	all
>Description:

	The internal code in pax assumes that write errors will be
	detected and thus SIGPIPE can be ignored.

	However this is not true for the listing modes (-t and -v).

	When "pax -v" output is piped to "head" or "less", etc. and the
	viewing is stopped well before pax is done then the command
	"hangs" until the whole archive is read instead of immediatly
	quitting as follows:

	$ gzcat .../binary/sets/base.tgz | pax -v | head
	drwxr-xr-x  2 root     wheel          0 Jun 22 14:58 .
	drwxr-xr-x  2 root     wheel          0 Jun 21 21:55 ./altroot
	drwxr-xr-x  2 root     wheel          0 Jun 22 14:52 ./bin
	-r-xr-xr-x  1 root     wheel     218504 Jun 21 17:36 ./bin/awk
	-r-xr-xr-x  1 root     wheel      76649 Jun 21 17:36 ./bin/cat
	-r-xr-xr-x  1 root     wheel      79587 Jun 21 17:36 ./bin/chio
	-r-xr-xr-x  1 root     wheel      90868 Jun 21 17:36 ./bin/chmod
	-r-xr-xr-x  1 root     wheel      94698 Jun 21 17:36 ./bin/cp
	-r-xr-xr-x  1 root     wheel      99661 Jun 21 17:36 ./bin/date
	-r-xr-xr-x  1 root     wheel     109261 Jun 21 17:36 ./bin/dd
	pax: Listing incomplete. (Broken pipe)

>How-To-Repeat:

	get really annoyed one last time that pax still doesn't honour
	SIGPIPE when listing large archives

>Fix:

Index: ar_subs.c
===================================================================
RCS file: /cvs/master/m-NetBSD/main/src/bin/pax/ar_subs.c,v
retrieving revision 1.31
diff -u -r1.31 ar_subs.c
--- ar_subs.c	22 Aug 2004 16:46:18 -0000	1.31
+++ ar_subs.c	10 Oct 2004 20:13:22 -0000
@@ -143,6 +143,16 @@
 				break;
 			if (res == 0)
 				ls_list(arcn, now, stdout);
+			/*
+			 * if there's an error writing to stdout then we must
+			 * stop now -- we're probably writing to a pipe that
+			 * has been closed by the reader.
+			 */
+			if (ferror(stdout)) {
+				syswarn((errno == EPIPE) ? 0 : 1,
+					errno, "Listing incomplete.");
+				break;
+			}
 		}
 		/*
 		 * skip to next archive format header using values calculated

>Release-Note:
>Audit-Trail:
>Unformatted: