Hello,
  I'm having some trouble with a perl script I'm writing.

when I try to execute something on the command line, it
just plain *doesn't work* i've used system & backticks (`).
No luck, when I use (`) i get no output either...

the command is:

system("/sbin/mkfs -t xfs $device");
if (!?) { print "Failed! - $?\n"; }

[download]


Failed! 13

It's that simple. I'm using system in other parts of this
script and it works fine. I can even verify the system 
call is working, by creating a wrapper script. like so:

(make_fs.pl)
-------------------------------------------------------

#!/usr/bin/perl -w

my $device = $ARGV[0];

print "I GOT $device !!\n";
system("/sbin/mkfs -t xfs $device");
exit($?);

[download]


--------------------------------------------------------
(in the main script)
--------------------------------------------------------

#system("/sbin/mkfs -t xfs $device");
system("./make_fs.pl $device");
if (!?) { print "Failed! - $?\n"; }

[download]


I GOT /dev/exampledevice0
Failed - 13

--------------------------------------------------------

Same, exit code, and the command never ran. the reason I
know this is because. if, on the command line, I run that
exact same command:

# /sbin/mkfs -t xfs /dev/exampledevice0

the program formats it, if it had already been formatted
it would ask for me to do a --force. So this is the first
time it's been formatted.

the script _is_ running as root. and when I print the
$! output, it just says "illegal seek".

now, if I use backticks (`) instead, this is what happens:


#system("/sbin/mkfs -t xfs $device");
#system("./make_fs.pl $device");
print `/sbin/mkfs -t xfs $device`;
if (!?) { print "Failed! - $?\n"; }

[download]


Failed! - 13

(no output from the first print)

I have been coding in perl for over 2 years and never had
this problem before. Any help GREATLY appreciated!

- Nick

In reply to calling an external program, from within a perl script by nick

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