Equate File Handles?

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

Is there any possible way of equating file handles?

My program takes in any number of files including a '-' or none which would then read from STDIN. The problem is, i'm doing something like so:

foreach $file (@files) {
   if ((!open (FILE, "<file")) && ($file ne '-'))
   {
        #print error and die
   }
   else 
   {
      while ($line = <FILE>) #OR if FILE is undefined then <STDIN> {
           #do something
        }
   }
}
[download]

I'd like to be able to just make FILE equal STDIN before so i don't have to fiddle around with anything in the condition of the loop. (Unless it happens to be really nice and simple to do it in the condition).

Comment on Equate File Handles? Download Code

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Re: Equate File Handles? by ikegami (Patriarch) on May 07, 2009 at 02:58 UTC
Don't you simply want `open(FILE, $file)`? `$ echo foo > foo.txt $ perl -e'open FILE, $ARGV[0] or die $!; print <FILE>' foo.txt foo $ echo foo \| perl -e'open FILE, $ARGV[0] or die $!; print <FILE>' - foo $ perl -e'open FILE, $ARGV[0] or die $!; print <FILE>' 'echo foo \|' foo $ perl -e'open FILE, $ARGV[0] or die $!; print <FILE>' 'cat foo.txt \|' foo` [download] If you want `STDIN` to be the default, prepend `@ARGV = '-' if !@ARGV;`. `$ echo foo \| perl -e'@ARGV = "-" if !@ARGV; open FILE, $ARGV[0] or die + $!; print <FILE>' foo` [download] Perl does all of this for you when you use `<ARGV>` or its shorter form `<>`. `$ perl -e'print <>' foo.txt foo $ echo foo \| perl -e'print <>' - foo $ echo foo \| perl -e'print <>' foo $ perl -e'print <>' 'echo foo \|' foo $ perl -e'print <>' 'cat foo.txt \|' foo` [download] Is there any possible way of equating file handles? Equating? Sounds like comparing, but I think you mean assigning. If so, yes. `FILE` is short for `FILE`. If you use the latter form, you'll have no problem. `FILE = STDIN; $fh = STDIN; $fh = \*STDIN; # Ref often allowed and even preferred.` [download]	[reply] [d/l] [select]
Re: Equate File Handles? by Anonymous Monk on May 07, 2009 at 02:39 UTC
Okay so it's working. But i'm not sure why. I've done absolutely nothing to the code except add '-' to @files if wanted. Does <FILE> automatically go to STDIN if undefined?	[reply]