Capturing input from pipe?

lowlife has asked for the wisdom of the Perl Monks concerning the following question:

I want to write a script which captures input from a pipe. E.g.

% echo "bla" | myscript.pl
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Originally posted as a Categorized Question.

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Re: Capturing input from pipe? by tomhukins (Curate) on Apr 27, 2001 at 18:46 UTC
A pipe passes the output of one command to the input of another. So, to read the output of your `echo` command, read from STDIN. An example myscript.pl might be: `#!/usr/bin/perl print <>;` [download]	[reply] [d/l] [select]
Re: Capturing input from pipe? by ariels (Curate) on May 01, 2001 at 14:20 UTC
If you want to read only the standard input, you can read the predefined filehandle `STDIN`. For instance, to add line numbers to all lines coming from your pipe, you could do this: `#!/usr/local/bin/perl -w use strict; while (<STDIN>) { print "$. $_" }` [download] But almost any program is more useful if it can read either STDIN or filenames supplied on the command line. So reading `<>` almost always makes more sense.	[reply] [d/l] [select]
Re: Capturing input from pipe? by hdp (Beadle) on Apr 27, 2001 at 19:03 UTC
Oft-used command line switches related to this subject are `-p`, `-n`, and `-a` (especially in conjunction with `-F`). See perlrun for how they work and what they do. hdp.	[reply] [d/l] [select]
Re: Capturing input from pipe? by lowlife (Initiate) on Apr 27, 2001 at 19:00 UTC
OK, that was a lot simpler than I thought but it works exactly like I want. Thanks a lot!	[reply]