How do I test if a file has write permission?

ChuckularOne has asked for the wisdom of the Perl Monks concerning the following question:

The -w test will do:

if (-w FILEHANDLE) {
    print "It's writeable by my effective uid or gid!\n";
}
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This code was credited to chromatic by the author. --Ed.

Originally posted as a Categorized Question.

Comment on How do I test if a file has write permission? Download Code

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Re: How do I test if a file has write permission? by fx (Pilgrim) on Dec 19, 2003 at 23:35 UTC
Another, but probably less efficient way, is to open the file in append mode. If the open fails the file COULD be read-only: `open(FILE, ">>some_file.txt") \|\| print "File is read only";` The advantage of this way, I suppose, is that if you really want to write things to the end of the file then it's now open :)	[reply] [d/l]
Re: Answer: How do I test if a file has write permission? by exussum0 (Vicar) on Dec 20, 2003 at 20:58 UTC
Open fails when it can't write, period. So if a directory where a file is expected or you have an NFS timeout, this will fail for non-permission reasons. (Why would your current directory be missing? If someone else rm's it of course :) Play that funky music white boy..	[reply]