On Wed, Jul 03, 2002 at 01:15:39AM +0800, Connie Chan wrote:
> For pure perl Code, you may try :
> if (-e "filename") { print "existed" }
> else { open (FH, ">filename"); ...... ; close (FH)}This is a bad idea, as you've introduced a race condition. What happens if I symlink 'filename' to some important file in between the time you check if it exists and open it? > For temp files, you may try using time, plus > users IP, that would near 0% that you will > have the risk to write to an existed file... This works if you're the only one dealing with the file, but once you introduce other, possibly malicious, users into the mix you have to worry about security. It may be that he's dealing with the file in this manner, but he doesn't specify in his question, and it's better to be safe than exploited. See my response to the original poster for better ways of opening files safely, and creating temporary files. Michael -- Administrator www.shoebox.net Programmer, System Administrator www.gallanttech.com -- -- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
