in reply to Re: Filenames based on timestamp
in thread Filenames based on timestamp

This is prone to race conditions when several processes are involved. Between the -e test and the actual file creation, a file of the name in question may have been created by another process.

Makeshifts last the longest.

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Re: Re: Re: Filenames based on timestamp
by robobunny (Friar) on Jun 27, 2002 at 17:21 UTC
    that's true. you could work around that by also included a PID in the filename. 
      while(-e "$time_$$_$counter") { $counter++; }
  open(F, ">$time_$$_$counter");

    [download]
    of course, then the filenames won't necessarily be in ascending order chronologically.
[reply]
[d/l]
      what about multiple threads :-)

      page 572-574 of camel3 suggests something along the lines of... 
      $fn = "filename_20020723141223_";
my $c = 1;
do {
    $fn .= "$c";
    $c++;
} until sysopen(FH, $fn, O_RDWR | O_CREAT | O_EXCL, 0600);
# now do I/O using $fh handle...

      [download]
[reply]
[d/l]

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