A few other tips. When you take input from the keyboard you probably want to output a prompt to the user. This looks a bit dumb if the user redirected the input from a file (< in the shell) or another program using a pipe (prog|yours.pl). You can test if STDIN (or any other file handle) is connected to a terminal with:
if (-t STDIN) { 
   # output prompt
}

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This is also useful before you pipe to more(1). You can pipe to more(1) from within your program automatically if connected to a terminal:
my $old_handle;
if (-t STDOUT) { 
   open (MORE, "| more") or die "No more $!\n";
   $old_handle = select MORE;
}

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At the end of the program:
END {
   if (defined $old_handle) {
      select $old_handle;
      close MORE;
   }
}

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In reply to Re: How do I pipe the output of a Perl program to something else? by cdarke
in thread How do I pipe the output of a Perl program to something else? by azredwing

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