Re^2: How to know the status of a command invoked by open function?

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Re^3: How to know the status of a command invoked by open function? by ikegami (Patriarch) on Aug 16, 2011 at 01:01 UTC
[ Please don't use `<pre>...</pre>`. Use `<p>` at the start of paragraphs and use `<c>...</c>` around computer text (code, data, output, etc). ] why the following two opens have different result? `open(PS,"ls . 2>/dev/null \|")` [download] is equivalent to `open(PS, '-\|', /bin/sh', '-c', 'ls . 2>/dev/null ')` [download] but `open(PS,"ls . \|")` [download] get optimised to `open(PS, '-\|', 'ls', '.')` [download] Also see the update to my original reply. But how can i get the exit status for the command in this case? You already know how. It's in `$?` after a successful `close`. In this case, it's 141. The shell returns 141 (`128\|SIGPIPE`) when its child dies from SIGPIPE.	[reply] [d/l] [select]
Re^4: How to know the status of a command invoked by open function? by zhujian0805 (Sexton) on Aug 16, 2011 at 01:21 UTC
it's weird that i get return code '0' when i run my script on AIX.	[reply]
Re^5: How to know the status of a command invoked by open function? by ikegami (Patriarch) on Aug 16, 2011 at 01:42 UTC
Yes, very weird. You'd get zero if `ls` managed to finish before `close` closed the pipe, but that's not very likely. Or maybe AIX processes in general or AIX's `ls` specifically behave differently when they encounter a closed pipe. Or maybe the shell doesn't relay the death of the child to its parent in AIX. On AIX, what output do you get from `/bin/sh -c 'perl -e'\''kill TERM => $$'\''' ; echo $?` [download]	[reply] [d/l] [select]
Re^6: How to know the status of a command invoked by open function? by zhujian0805 (Sexton) on Aug 16, 2011 at 01:56 UTC
Re^7: How to know the status of a command invoked by open function? by ikegami (Patriarch) on Aug 16, 2011 at 02:39 UTC