Perl: How to check if there is something being piped in
Hi,
I am somewhat new to Perl and currently checking it out. I have a problem testing, if there is nothing being piped in to that script.
I am reading input from STDIN this way:
In other words, my script works fine but when there is nothing being piped in, it just stops and waits for input.
I have tried several things I found on different pages but I wasn't able to get it to work.
Is there a simple way to check and avoid this?
Thanks in forward!
Last edited by zaxxon; 10-25-2012 at 09:25 AM..
Reason: spelling
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Discussion started by: alex_5161
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LEARN ABOUT FREEBSD
atf-sh
ATF-SH(1) BSD General Commands Manual ATF-SH(1)NAME
atf-sh [-s shell] -- interpreter for shell-based test programs
SYNOPSIS
atf-sh script
DESCRIPTION
atf-sh is an interpreter that runs the test program given in script after loading the atf-sh(3) library.
atf-sh is not a real interpreter though: it is just a wrapper around the system-wide shell defined by ATF_SHELL. atf-sh executes the inter-
preter, loads the atf-sh(3) library and then runs the script. You must consider atf-sh to be a POSIX shell by default and thus should not
use any non-standard extensions.
The following options are available:
-s shell Specifies the shell to use instead of the value provided by ATF_SHELL.
ENVIRONMENT
ATF_LIBEXECDIR Overrides the builtin directory where atf-sh is located. Should not be overridden other than for testing purposes.
ATF_PKGDATADIR Overrides the builtin directory where libatf-sh.subr is located. Should not be overridden other than for testing purposes.
ATF_SHELL Path to the system shell to be used in the generated scripts. Scripts must not rely on this variable being set to select a
specific interpreter.
EXAMPLES
Scripts using atf-sh(3) should start with:
#! /usr/bin/env atf-sh
Alternatively, if you want to explicitly choose a shell interpreter, you cannot rely on env(1) to find atf-sh. Instead, you have to hardcode
the path to atf-sh in the script and then use the -s option afterwards as a single parameter:
#! /path/to/bin/atf-sh -s/bin/bash
ENVIRONMENT
ATF_SHELL Path to the system shell to be used in the generated scripts.
SEE ALSO atf-sh(3)BSD September 27, 2014 BSD