-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Yes you are correct. Calling stat is more efficient than opening a file. The reason? To stat a file, the OS simply needs to look up information in the filesystem structures and return it. To open a file, the system actually has to allocate a file handle, associate it with a stream, etc. etc. etc. Needless to say, less work is involved for stat. - --- Joseph C. Lininger jbahm at pcdesk.net note, the following is used for automated processing. Please leave in tact if quoting me in a reply. Verification: 5eab38a77ac40416e075be8f50607ff7 - ----- Original Message ----- From: "Thomas Stivers" <stivers_t@xxxxxxxxxxxxxxxxx> To: <speakup at braille.uwo.ca> Sent: Saturday, May 15, 2004 5:59 AM Subject: Re: directory listings in programs > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > On May 15 2004 1:35 AM, Gregory Nowak wrote: >> Hi all. >> >> I am writing a c program under gnu/Linux, in which I need to know if a >> file of a particular name exists. The only way I can think of checking >> for this is to attempt to open a file of a given name in read-only >> mode. If it opens, the file exists, if the FILE stream is NULL, the >> file doesn't exist. However, doing this for a good number of files >> would be inefficient in my opinion. So, I was wondering if there is a >> function which will simply tell me if a file of a given name exists or >> not, sort of like calling ls, although I don't actually want to be >> literally doing that either from within the program? Thanks. > > It does a lot more than you're asking for, but I think the stat system > call is what you're after. Check out man 2 stat for details. If I have > understood things corectly stat'ing a file is more efficient than opening > it. > > - -- > "Debugging is twice as hard as writing the code in the first place. > Therefore, if you write the code as cleverly as possible, you are, > by definition, not smart enough to debug it." - Brian W. Kernighan > > Thomas Stivers e-mail: stivers_t at tomass.dyndns.org > -----BEGIN PGP SIGNATURE----- > Version: GnuPG v1.2.4 (GNU/Linux) > > iD8DBQFApgY+5JK61UXLur0RAoJzAJ9AWfQURyehNJgT0lq+iXq/M3tbowCfamaI > 5jll+3k7QEKCUNbW47bYyVk= > =f0t1 > -----END PGP SIGNATURE----- > > _______________________________________________ > Speakup mailing list > Speakup at braille.uwo.ca > http://speech.braille.uwo.ca/mailman/listinfo/speakup > -----BEGIN PGP SIGNATURE----- Version: PGP 8.0.3 iQA/AwUBQKdXkSenap9Jqj2wEQLS4QCfRWftRwGLlT5uryiBMlxXmQN5ZLgAoIUd wGh1vbbKHsdhI3U2rQ9UEtqz =6o2b -----END PGP SIGNATURE-----
