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System calls tend to make a little uneasy.

Today I needed to do mkdir in the middle of something unwieldy and I thought, uh oh, how do I error check against this.

perlfunc mkdir wasn't real helpful, and perlmonks didn't pop anything up right away either.

My shortcut was to use the google "site:" syntax to search repository of merlyn articles

There, in the third result, was my answer. Since google gives such nice summaries, with the key words bolded for easier viewing, I saw it right away: -d $CORRUPT or mkdir $CORRUPT, 0755 or die "Cannot mkdir $CORRUPT: $!";

So, that's all.

If there's ever a bit of idiom that you *almost* know, but can't quite nail, and you're too shy to ask on the chatterbox, do a site query on or (who else is good for this?) and sometimes the answer pops right out.

Cheers :)


UPDATE: Actually, though, what I really wanted was

#!/usr/bin/perl use strict; use warnings; my $log_dir="/root/blee"; my $result = system("mkdir -p $log_dir"); print "result: $result\n"; -d $log_dir or system("mkdir -p $log_dir") && die "couldn't make $log_ +dir: $!"; print "error: should have died already\n";

Because system returns 0 on success, whereas perl mkdir returns 0 on failure.

So much for magic bullets ;)

In reply to How to find code written by smart people by tphyahoo

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