Backticks to capture umask output

austin43 has asked for the wisdom of the Perl Monks concerning the following question:

Good day monks, I have a quick question. I am trying to use the output of umask to print output with the following code.

$confirm_SysUmask = `umask`;

    if ($confirm_SysUmask =~ m/^0037$/)
    {
                #if umask output equals 0037
        print "SUCCESS: System umask set correctly ($confirm_SysUmask)
+\n";
    }
    else
    {
                #if umask output not equal to 0037
        print "ERROR: System umask incorrect ($confirm_SysUmask)\n";
    }
[download]

For some reason the string won't capture the output of umask. (The string just shows up blank)Is there something I'm missing? Thanks in advance.

Comment on Backticks to capture umask output Download Code

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Re: Backticks to capture umask output by saberworks (Curate) on May 24, 2011 at 20:46 UTC
I recommend you: `use warnings; use strict;` [download] This will tell you exactly what the problem is. On my system I get this: Can't exec "umask": No such file or directory at umask.pl line 4. `$ which umask` [download] Indicates that it's not an actual command you can call. Why aren't you just using the umask perl function? umask Sets the umask for the process to EXPR and returns the previous value. If EXPR is omitted, merely returns the current umask.	[reply] [d/l] [select]
Re: Backticks to capture umask output by ikegami (Patriarch) on May 24, 2011 at 20:49 UTC
There is no `umask` executable. $ perl -E'say `umask` // ( $! != -1 ? $! : sprintf("\$?=%04x", $?) );' No such file or directory [download] You are trying to execute a bourne shell command without involving a bourne shell. So invoke the shell: $ perl -E'say `/bin/sh -c umask` // ( $! != -1 ? $! : sprintf("\$?=%04 +x", $?) );' 0077 [download] Of course, you should just use the builtin `umask`. `$ perl -E'my $umask = umask; say defined($umask) ? sprintf("%04o", $um +ask) : $!;' 0077` [download]	[reply] [d/l] [select]
Re^2: Backticks to capture umask output by austin43 (Acolyte) on May 24, 2011 at 20:58 UTC
Nevermind I get what you're saying. I tried invoking /bin/sh and it worked! Thanks alot.	[reply]
Re^2: Backticks to capture umask output by austin43 (Acolyte) on May 24, 2011 at 20:56 UTC
When I type 'umask' into the terminal (using bash) it outputs 0037 though...	[reply]
Re^3: Backticks to capture umask output by ikegami (Patriarch) on May 24, 2011 at 20:59 UTC
So use «`/bin/bash -c umask`» instead of «`/bin/sh -c umask`»	[reply] [d/l] [select]
Re^3: Backticks to capture umask output by ikegami (Patriarch) on May 24, 2011 at 20:58 UTC
Yes, but what's your point?	[reply]


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