stop process based on exit status.

chandu76 has asked for the wisdom of the Perl Monks concerning the following question:

how can exit based on exit code?

open(FILE,"run_tool -f "test.tcl" 2>&1|");
open(LOG,">log");
while(<TEMP>){
print;
print log;
}
[download]

if test.tcl file not exists then tool is invoked and it is hanged.how can I come out of while loop. or another case is if did not use exit in tcl script the same problem tool runs and hangs. how can I exit in such situations? I can't use " exit 1 if ($_ =~ /^(Error :)); " becuase tool should run though it gets error messages,but should exit depending on exit status.

Comment on stop process based on exit status. Download Code

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Re: stop process based on exit status. by jdalbec (Deacon) on Aug 14, 2004 at 13:27 UTC
You have a bareword `test.tcl` in your code. Also, you open `FILE` but you then read from `TEMP`. You should always `use strict; use warnings;` [download] I don't think you can get an exit status from a pipe. If you're on nx you could try `open(FILE,'run_tool -f "test.tcl" 2>&1; echo Status code: $?\|');` [download] and `exit 1 if ($_ =~ /^Status code: [^0]/)` [download] I'm not sure how to do the equivalent in Windows. Another option is to use `-f` (see `man perlfunc`) to test whether the file exists before you run the command.	[reply] [d/l] [select]
Re: stop process based on exit status. by Mr_Person (Hermit) on Aug 14, 2004 at 16:22 UTC
This may be a little overblown for what you need, but it will capture both the STDOUT and the STDERR to a log file, die if the program does not exist, and display the return code. `#!/usr/bin/perl use strict; use warnings; use IPC::Run qw( start pump finish ); open(LOG, '>', 'log') or die "Unable to open log: $!"; my ($in, $out); my $h = start([ 'run_tool', '-f', 'test.tcl' ], \$in, \$out, \$out); while($h->pump) { print LOG $out; $out = ''; } $h->finish; close(LOG); print "Exit code was: " . $h->result . "\n";` [download] You'll probably want to take a closer look at the IPC::Run docs for more details on what all it can do. It also offers fairly flexible control over interactive programs if you want to do that in the future. I tend to use it over `open` or `system` any time I need to start doing anything more than just run the program.	[reply] [d/l] [select]