You need to elaborate on "fail to redirect" and "my code is failing". Do you not get an output file? Is the output file empty?
@files = <STDIN>;
You don't show how you are running your code, but that line might be causing your code to appear to hang until you enter Ctrl-C, or some such. Also, you keep clobbering your output "data" file for each input file. Maybe you want something more like: 
use warnings;
use strict;

for my $file (@ARGV) {
    print "Preforming sha1 on $file\n";
    system( "sha1sum $file >> data" );
}

[download]

Run it like: 

code.pl file1 file2 file3

[download]

In reply to Re: What is causing sha1 system call to fail to redirect? by toolic
in thread What is causing sha1 system call to fail to redirect? by Puregnome45

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