Re^3: create image via binmode

If the image is rather small, you could also try something like:

my $imageContent = do {
  open (my $IN, "<", $image) or die "Error in reading '$image': $!";
  binmode($IN);
  local $/ = undef;

  my $content = <$IN>;
  close($IN);
  return $content;
}; # do

open (my $OUT, ">", $outfile)
  or die "Error: couldn't write '$outfile': $!\n";
} # unless
binmode($OUT); # thanks to pKai
print $OUT $imageContent;
close($OUT) or die "Error: couldn't close '$outfile': $!";
[download]

or shorter:

my $imageContent = do {
  open (my $IN, "<", $image) or die "Error in reading '$image': $!";
  binmode($IN);
  local $/; # defaults to undef
  <$IN>; # close happens automatically at end of block if
         # you use a lexical variable as filehandle
}; # do

open (my $OUT, ">", $outfile) 
  or die "Error: couldn't write '$outfile': $!\n";
binmode($OUT); # thanks to pKai
print $OUT $imageContent;
close($OUT) or die "Error: couldn't close '$outfile': $!";
[download]

Best regards,
perl -e "s>>*F>e=>y)\*martinF)stronat)=>print,print v8.8.8.32.11.32"

Comment on Re^3: create image via binmode Select or Download Code

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Re^4: create image via binmode by pKai (Priest) on Jan 15, 2006 at 12:48 UTC
There is a `binmode $OUT;` missing, which will lead to rendering the output unusable under Win.	[reply] [d/l]
Re^4: create image via binmode by ikegami (Patriarch) on Jan 14, 2006 at 18:56 UTC
That's the same as my first post, except you added `do` which doubles the memory usage.	[reply] [d/l]
Re^5: create image via binmode by strat (Canon) on Jan 15, 2006 at 10:21 UTC
It's similar, but there are some differences (which may or may not be important): the local $/ has a very tight scope which may be important if you read additional files and don't want to get them in slurp mode. no global filehandles. a minimum of error handling filenames hardcoded only once well, you can also get point 1 with an ordinary block, e.g. `my ($content, $IN); unless (open ($IN, "<", $file)) { die "Error in reading '$file': $!\n"; } # unless else { local $/ = undef; # valid only until end of block binmode($IN); $content = <$IN>; close ($IN); } # else` [download] or the like. Global filehandles have a problem: they are global, and if you open(IN, ...) and another IN is already opened, the first IN is closed. In some cases (e.g. recursions, reading filenames out of a file and opening them in a subroutine) this may be fatal. point 4 is in my eyes important that it is not good to write something like: `unless (open ($IN, "<", "file1.txt")) { die "Error in reading 'file1.txt': $!\n"; } # unless` [download] because if the filename changes to something different, there is the danger you forget to change the filename in the die-message (or just do a stupid typo) and you or somebody else searches for the wrong problem Best regards, perl -e "s>>F>e=>y)\martinF)stronat)=>print,print v8.8.8.32.11.32"	[reply] [d/l] [select]
Re^6: create image via binmode by ikegami (Patriarch) on Jan 15, 2006 at 17:59 UTC
I agree with everything, and follow those practices myself. I just stopped reading after I read what I thought was the point of your post. ++'ed.	[reply] [d/l] [select]