Re: Subroutine Return Values

The 'system' will give you only the exit status not the STDOUT. See below the difference between backticks, system call and exec.

$var  = `ls`;
print "\n---\n $var \n---\n ";
The $var will have the output of 'ls' command.
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$var = system('ls');
print "\n---\n $var \n---\n ";
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In the above code, ls command will be executed and $var will have the zero value but not the output of the 'ls' command.

$var = exec('ls');
print "\n---\n $var \n---\n ";
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Here ls command will get executed but $var will have nothing. More, the program will get terminated after exec execution.
So I guess, you have to use backticks instead of system call.

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Re^2: Subroutine Return Values by ww (Archbishop) on Jan 12, 2007 at 16:16 UTC
This is either a nit, or ignorance, but... using AS 5.8.8 (819) on Win XP (gack, but no nx allowed at work), the last variant script in siva_kumar 's otherwise well-considered reply HANGS (as the knowledgable may well have expected). It appears that his word "program" refers to `ls` (which was replaced with `dir` for this win test) but that the statement "Here ls command will get executed but $var will have nothing." would be more precise if rephased to: "Here the ls command will be executed, but will never return control to the script. Hence, the line to print $var will never be executed." From perldoc perlfunc: `The "exec" function executes a system command and never returns-- use "system" instead of "exec" if you want it to return.`	[reply]
Re^3: Subroutine Return Values by siva kumar (Pilgrim) on Jan 18, 2007 at 07:19 UTC
Yes I agree. Thanks for comment.	[reply]