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From: "BJ" <baj2107 AT columbia DOT edu>
Subject:  file locking problem
Date:  Wed, 19 Sep 2007 19:30:26 -0400
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Message-ID: <fcsbji$bj0$1@sea.gmane.org>
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I have a file locking problem that is solved under Mac and Linux using
fcntl:
int lockRepFile (int fd, char lock, size_t from, size_t length) {
struct flock fl;

      fl.l_start = from;
      fl.l_len = length;
      fl.l_pid = 0;

      if (lock == 'r') fl.l_type = F_RDLCK;
      else if (lock == 'w')  fl.l_type = F_WRLCK;
      else if (lock == 'u')  fl.l_type = F_UNLCK;
      fl.l_whence = SEEK_SET;

      return (fcntl(fd, F_SETLKW, &fl));
}

Now, unfortunately this hangs occasionally using cygwin - gcc.

I would appreciate any comments and suggestions on how debug this and how to
improve the performance i.e. stop it from hanging...

Thanks

B







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