system() and output

hotshot has asked for the wisdom of the Perl Monks concerning the following question:

Hello there!

I need get the output from runing a script, so I used:

if (! open(OUTPUT, "$myScript |")) {
  # handle error
}
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OUTPUT is now a handler for the output generated by the script.
Now, I need also the exit status returned from the script, which I can get by:

$exitStatus = system($script);
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But this won't give me the output from the script.
Is there an effiecient way to get both the exit status and the output from the script (without using a temporary file)?

Thanks

Hotshot

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Re: system() and output by ctilmes (Vicar) on Aug 10, 2003 at 16:15 UTC
After reading what you want from OUTPUT, `close OUTPUT` returns false if $myScript fails or exits with non-zero. It also leaves the exit status in `$?`. see `perldoc -f close` for more information. Or you can use backquotes my $output = `$myScript`; which also leaves exit status in `$?`.	[reply] [d/l] [select]
Re: Re: system() and output by hotshot (Prior) on Aug 11, 2003 at 05:35 UTC
In your first suggestion, you said: close OUTPUT returns false if $myScript fails or exits with non-zero myScript returns 0 on success and non zero on failure, which is the opposite of what close() returns, what is returned on success of myScript and does the non-zero you mentioned are myScript exit statuses? And another thing, in your second suggestion, does $output holds the stdout from myScript? Thanks again Hotshot	[reply]
Re: system() and output by BrowserUk (Patriarch) on Aug 10, 2003 at 16:28 UTC
The easiest way would be to use IPC::Open2. This returns the pid of the process. Once you have the pid, you can use waitpid to retrieve the status. It is returned in perlvar:$?. You need to shift this >> 8 in order to extract the status value. P:\test>type test.pl #! perl -slw print 'Hello world'; exit 12; P:\test>perl -de1 Loading DB routines from perl5db.pl version 1.19 Editor support available. Enter h or `h h' for help, or `perldoc perldebug' for more help. main::(-e:1): 1 DB<1> use IPC::Open2 DB<2> $pid = open2( IN, OUT, 'perl58.exe test.pl') or warn $!; DB<3> print <IN>; Hello world DB<4> waitpid $pid, 0 DB<5> print $? >> 8; DB<6> 12 [download] Examine what is said, not who speaks. "Efficiency is intelligent laziness." -David Dunham "When I'm working on a problem, I never think about beauty. I think only how to solve the problem. But when I have finished, if the solution is not beautiful, I know it is wrong." -Richard Buckminster Fuller If I understand your problem, I can solve it! Of course, the same can be said for you.	[reply] [d/l]