Re: Determine if open(2) created or opened?

From: Casper H.S. Dik (Casper.Dik_at_Sun.COM)
Date: 12/27/03

  • Next message: Michael B Allen: "Re: Determine if open(2) created or opened?" 
    Date: 27 Dec 2003 10:06:25 GMT

    Michael B Allen <mba2000@ioplex.com> writes:

    >O_CREAT specifies that if the file does not exist it should be created
    >whereas if the file already exists it should simply be opened. How can it
    >be determined if the file was created or just opened?

    You can't; what you can do, however, is this:

            fd = open(path, O_WHATEVER);
            if (fd == -1 && errno == ENOENT) {
                    /* open failed, file didn't exist */
                    fd = open(path, O_WHATEVER|O_CREAT|O_EXCL, 0666);
            }

    Of course, the open can now fail if it was created in between,
    you could iterate.

    Casper 

    -- 
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Statements on Sun products included here are not gospel and may
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  • Next message: Michael B Allen: "Re: Determine if open(2) created or opened?"