On Jan 6, 2004, at 9:32 AM, [EMAIL PROTECTED] wrote: [..]
So, 1. from within perl.script, how can one tell if the input stream is coming from STDIN or a file that was opened by <>?
2. If input stream is not coming from STDIN, but a file, how can one tell which file is the current file (assuming multiple files were specified on the command line)?
This is gonna sound a bit silly, so laugh along with me while I play this out.
If you want to know which is the whom For What, why not simply code it that way?
As an illustration:
<http://www.wetware.com/drieux/pbl/perlTrick/CommandLine/ file_or_stdin.plx>
In this case I will walk the @ARGV if there is anything to walk, test that the file exists, then pass it off to a count_lines() function, which will open it and count the number of lines.
If there are no arguments at the command line, then we will call count_lines() without a file name.
On the inside of the count_lines() function is the trick
$file ||= '-'; # we open STDIN unless file
either we were passed a file name to open, or we will set $file to '-' so that it will read from STDIN.
cf: perldoc -f open
ciao drieux
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