in reply to Getting rid of extra outputs

How are you calling the external program?

If you are calling it like this

my $cmd = 'ls';
my $result = `$cmd`;

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..then consider the following approach:

my $cmd = 'ls 2>&1';
my $result = `$cmd`;

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The purpose of the 2>&1 is to take anything output to STDERR and redirect to STDOUT.

This will be of no use if your script is on a Win32 machine.

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Re^2: Getting rid of extra outputs
by sandrider (Acolyte) on May 27, 2005 at 07:57 UTC

    No I don't call it like that.

    It is a.so file that is called by a.pm module that is provided. I call the external.pm and it calls the external.so file.

    When I run it via command line I get things like buffering 10000... and then after the results will be returned. I have a feeling that when I do a use external, it makes those statements. Is there a work around w/o having to edit external.pm? I don't want to mess about with another persons script.

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      Seems like you want to temporarily redirect STDOUT to somewhere else?

      You'll find lots of good stuff if you Super Search here for "redirect stdout" or similar.

      This is a VERY basic way of doing it, which might get you started:

      print "This goes to stdout\n";
{
    local *STDOUT;
    open STDOUT, '>/tmp/myoutput';
    print "This gets redirected\n";
    # more code here that prints stuff to stdout
}
print "Back to normal stdout\n";

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      If you really don't need the output of your external.pm then change /tmp/myoutput to /dev/null (if you're on Unix).

      Disclaimer: I've never actually used techniques like this in real code, there may be problems/caveats etc. Searching this site should turn up more robust solutions!

      s^^unp(;75N=&9I<V@`ack(u,^;s|\(.+\`|"$`$'\"$&\"\)"|ee;/m.+h/&&print$&
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