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I am writing a large Perl script, which needs to utilize other existing Perl scripts. The problem is the main script needs to reference many different scripts from different folders. For example the main script would be contained in:

/perl/programs/io

It may need to run a script which is stored in:

/perl/programs/tools

Note that there are other orthogonal folders besides tools so I need to be able to access any of them on the fly.

Currently this is what I got:

my $mynumber = '../tools/convert.pl bin2dec 1011';

In theory it should move back from the io directory then enter the appropriate tool directory and call the convert.pl script while passing it the parameters.

All this does is store the string in the single quotes to $myNumber.

Benjamin W.
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cjhutton
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    Uhhh... you're just assigning a string to a variable. Perhaps you meant to use [backticks](http://perldoc.perl.org/perlop.html#%60_STRING_%60)? – Matt Jacob Jan 27 '16 at 21:34
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    Possible duplicate of [How do I run a Perl script from within a Perl script?](http://stackoverflow.com/questions/364842/how-do-i-run-a-perl-script-from-within-a-perl-script) – Matt Jacob Jan 27 '16 at 21:36
  • @MattJacob yes, but the accepted answer there is a bit overkill for this case. – simbabque Jan 28 '16 at 10:37
  • @simbabque The accepted answer, perhaps. But there are other answers within that thread that do answer this question (and the question is the same). – Matt Jacob Jan 28 '16 at 17:15
  • @m, I agree, but my vote would hammer it, so I didn't. – simbabque Jan 28 '16 at 18:24

3 Answers3

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I like to assign the output of a command to an array so I can loop through the array to find error or other messages. For example if I'm making a zip file to email to someone I want to check to see if the zip program had any errors before I continue to make and send the email. 

@msgs = `zip -f myfile.zip *.pl`; # Use backticks

You can also assign the output to a scalar:

$msg = `ls -al *.pl`; # Use backticks
Bulrush
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To run any system command or script all you have to do is use `backticks`. From observing another programer's perl code, I misread these strange quotes for 'single quotes'.

backticks are also nice because they return the text in STDOUT to your perl script so that the output can be assigned to a variable, something I have found impossible if using system("");

cjhutton
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The similar question answer does not work with my version of perl. The line 

use IPC::System::Simple qw(system capture);

throws some errors. However just using system works, like this:

my $mynumber = system($^X, "../tools/convert.pl", 'bin2dec', '1011');

I can use the above without setting equal to something to execute scripts which return no value and are only sent arguments.

This seems to be the easiest way to do what I need to and the entire programs folder can be moved anywhere and it will still work as no parent directories above programs are used.

cjhutton
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