Quoting issues in the backticks aside, it might be worth the 4 extra lines of code to simply open a pipe from ps and do the winnowing and line counting yourself in your Perl rather than piping to the external commands.

open( my $ps_fh, "-|", "ps -ef" ) or die "Can't open pipe from ps: $!\
+n";
my $load = 0;
while( <$ps_fh> ) {
  $load++ if /somecmnd\.exe$/;
}
close( $ps_fh );
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On my system, your code produces this error:

sh: -c: line 0: unexpected EOF while looking for matching `''
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Backticks interpolate like double quotes, so you need to escape the $

my @load = `ps -ef | grep neversaint | grep 'somecmnd.exe\$' | wc -l`;
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You are interpolating the contents of Perl's post match special variable $' into your backticks string. Is that what you intend?

my $cmd = "some command";
print "$cmd\n"; # comment out later
my $res = qx{$cmd};
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Or use Smart::Comments and comment it out to begin with (then just run with perl -MSmart::Comments='###' mycode.pl when you want to see what's in it)

my $cmd = "blah"
### $cmd
my $res = qx/$cmd/;
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We're looking for a Perl and Database Developer for Corporate Investments Group.

Nowadays you can use readpipe() instead of backticks. You use readpipe() just as any other function, so you can use single quotes to avoid any interpolation.

lodin

Are you sure that you want to invoke ps, grep and wc without a full path? This may be a security issue.

And why do you start five processes (shell, ps, 2x grep, and wc) where one is sufficient? grep and wc can easily be done in Perl, without a new process. The shell does not have to be invoked, you can use exec "/bin/ps","-ef";. You just have to read the output from that process, see Safe Pipe Opens in perlipc, especially the "safe backtick or pipe open for read" example. Replace the while loop in the parent process with an array read plus two Perl greps, and finally use scalar @array to get the line count.