Here is one that has been making me think...
I need to execute a system program within a script where I can supply data to stdin and get back a return value. Normally I'd just do the following:

$prog = "/var/qmail/bin/qmail-remote";
$msg = "this is the email message";
$value = system($prog);

But, the program expects data (a mail message) from STDIN. Since I have the data in $msg I could do:

$prog = "/var/qmail/bin/qmail-remote";
$msg = "this is the email message";
open (OUT, "|$prog");
print OUT $msg;
close(OUT);

but this doesn't give me the much needed return code. Do any of you knw the best way to run a system program in a way that I can supply STDIN data and see a return value? I'd rather not write $msg to a file and do:
system("cat $file | $prog");
Thanks Terry

In reply to system(program) or open( by terry

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