fd.c

   1 #include "para.h"
   2 #include "error.h"
   3 /**
   4  * check whether a file exists
   5  *
   6  * \param fn the file name
   7  *
   8  * \return Non-zero iff file exists.
   9  */
  10 int file_exists(const char *fn)
  11 {
  12         struct stat statbuf;
  13
  14         return !stat(fn, &statbuf);
  15 }
  16
  17 int para_select(int n, fd_set *readfds, fd_set *writefds,
  18                 struct timeval *timeout)
  19 {
  20         int ret, err;
  21         do {
  22                 ret = select(n, readfds, writefds, NULL, timeout);
  23                 err = errno;
  24         } while (ret < 0 && errno == EINTR);
  25         if (ret < 0)
  26                 PARA_CRIT_LOG("select error (%s)\n", strerror(err));
  27         return ret;
  28 }
  29
  30 int mark_fd_nonblock(int fd)
  31 {
  32         int flags = fcntl(fd, F_GETFL);
  33         if (flags < 0)
  34                 return -E_F_GETFL;
  35         if (fcntl(fd, F_SETFL, ((long)flags) | O_NONBLOCK) < 0)
  36                 return -E_F_SETFL;
  37         return 1;
  38 }
  39