while( <> ){
  split /,/;
  print pack 'A10'x (scalar @_), @_;
}
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See the docs for while, split and pack. You can accomplish similar things with sprintf (as pack stuff is pretty complicated if you're not used to perl). You might wanna check perldata and perlvar as well.

Hope this helps,

Jeroen
"We are not alone"(FZ)
Updated, typo fixed thanks particle.

i think jeroenes means DBD::CSV

~Particle

OK, taking a great leap, here's what I would suggest:

• Get and install the Text::CSV module to read in the file. If you attempt to write your own csv-separator you will probably not handle embedded commas and strings correctly. Also, merlyn, who has more ESP than others, will find you and smite you heavily for re-inventing wheels.
• Use printf with fixed sizes to output records. That is, every specifier in your format should be preceded with a length.

To mis-quote Tom Christiansen: this reply may be somewhat sub-serious, but when you ask a vague question, you should expect a bit of whimsy.

HTH

An important addition to the use of (s)printf because it is not used everyday (but you can read it in the excellent tutorial Using (s)printf() by reptile). In order to enforce a field width of e.g. 3 for a string you have to use:

printf "%3.3s\n", 'Ho';
printf "%3.3s\n", 'Hogfather'
printf "%3s\n",   'Hogfather';

# this prints 
 Ho
Hog
Hogfather
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Update: Of course maybe it's not such a good idea to silently throw away part of the fields - so you should check the length of them beforehand. But this depends on your purpose ...

-- Hofmator