Re^3: reading files to different output files.

To expand a bit on the correct diagnosis of Anonymous Monk, you are opening the files, but you are not reading from them.

You are trying to read STDIN twice, once here:

my @in = <>;
[download]

and once here:

while ( <> ){
...
}
[download]

It's not clear to me what that is supposed to achieve.

Then you try to open a filehandle to a list:

open (READ, @in) || die "cannot open @in: $!.\n";
[download]

This suggests that you only have a single filename in @in, and that filename does not have a newline appended.

Your program logic alltogether is a bit weird, because in your while loop, you recreate your output files on every pass through the loop. This is most likely not what you want:

while ( <> ){
    for (my $i=0; $i<=$#file_names; $i++){
...
    }
}
[download]

Let me suggest a different structure of your program:

Open the output file(s)
For each input file
Open the input file
Read one line from the input file
Write the line to the output file(s)
Repeat reading

You have many parts of that already, but your program isn't structured in the right order.

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Re^4: reading files to different output files. by ic23oluk (Sexton) on May 31, 2017 at 14:25 UTC
first of all, thank you for your effort :) I wrote another program and I'm sure I am nearer to the solution than ever. However, it doesn't do anything: `#! usr/bin/perl use strict; use warnings; use IO::File; my @out; my @file_names = ("output1.txt", "output2.txt", "output3.txt"); my $i = 0; while (<>){ foreach (@ARGV){ open (READ, $ARGV) \|\| die "Cannot open $ARGV: $!.\n"; $out[$i] = IO::File->new( ">file_names[$i]" ) \|\| die "Cannot o +pen file_names[$i]: $!.\n"; $i++; while ( <READ> ){ print {$out[$i]} "$_"; } } }` [download] so what's the problem?	[reply] [d/l]
Re^5: reading files to different output files. by choroba (Cardinal) on May 31, 2017 at 14:53 UTC
~~Where do you use `@file_names` ?~~ `foreach (@ARGV)` sets $_ to the script arguments, where do you use `$_` ? ($q=q:Sq=~/;[c](.)(.)/;chr(-\|\|-\|5+lengthSq)`"S\|oS2"`map{chr \|+ord }map{substrSq`S_+\|`\|}3E\|-\|`7**2-3:)=~y+S\|`+$1,++print+eval$q,q,a, [download]	[reply] [d/l] [select]
Re^5: reading files to different output files. by shmem (Chancellor) on May 31, 2017 at 15:40 UTC
Do you get an error message? If so, why don't you post it? so what's the problem? The problem is that you are getting things mixed up. So several problems: You loop `foreach (@ARGV)` and use `$ARGV` instead of `$_` in the inner loop. You assign to `$out[$i]`, then increment $i, then access `$out[$i]` - which is undefined. Bummer. You need not stuff the filehandle into `@out`, since you are only using one output filehandle each time through. Use a lexical filehandle e.g. `my $outfh = IO::File->new(...)` You are missing a `$` in the expression `">file_names[$i]"` - that should be `">$file_names[$i]". Same in the subsequent argument to <c>die`.</c> Having fixed that: `while (<>){` [download] This loop reads all files on the commandline line by line, file after file and executes the code enclosed in the loop body, for every line from all files. Inside the while loop, you iterate over all files again with the `foreach(ARGV)` inner loop, opening and reading them. You open, read, write all files over and over as many times as all the files have lines, always incrementing `$i` which gets you quickly past the end of `@file_names`. Drop the outer `while (<>)` loop. update: But why am I writing you, at all? You didn't give a damn at Re: reading files to different output files., so what... perl -le'print map{pack c,($-++?1:13)+ord}split//,ESEL'	[reply] [d/l] [select]
Re^4: reading files to different output files. by ic23oluk (Sexton) on May 31, 2017 at 15:18 UTC
I finally solved it :) Thank you all, great community! here's my solution: `#! usr/bin/perl use strict; use warnings; use IO::File; my @out; my @file_names = ("output1.txt", "output2.txt", "output3.txt"); my $i = 0; my $file; if ($#ARGV < 1){ die "Usage: $0 Argument1 Argument2 ... \n"; } foreach $file (@ARGV){ open (READ, $file) \|\| die "Cannot open $file: $!.\n"; $out[$i] = IO::File->new( ">$file_names[$i]" ) \|\| die "Cannot open + $file_names[$i]: $!.\n"; while (my $line = <READ> ){ print {$out[$i]} "$line"; } $i++; }` [download]	[reply] [d/l]