npipe.c
上传用户:mei_mei897
上传日期:2007-01-05
资源大小:82k
文件大小:4k
- /* -------------------------------------------------------------------- */
- /* SMS Client, send messages to mobile phones and pagers */
- /* */
- /* npipe.c */
- /* */
- /* Copyright (C) 1997,1998 Angelo Masci */
- /* */
- /* This library is free software; you can redistribute it and/or */
- /* modify it under the terms of the GNU Library General Public */
- /* License as published by the Free Software Foundation; either */
- /* version 2 of the License, or (at your option) any later version. */
- /* */
- /* This library is distributed in the hope that it will be useful, */
- /* but WITHOUT ANY WARRANTY; without even the implied warranty of */
- /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU */
- /* Library General Public License for more details. */
- /* */
- /* You should have received a copy of the GNU Library General Public */
- /* License along with this library; if not, write to the Free */
- /* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
- /* */
- /* You can contact the author at this e-mail address: */
- /* */
- /* angelo@styx.demon.co.uk */
- /* */
- /* -------------------------------------------------------------------- */
- /* $Id$
- -------------------------------------------------------------------- */
- #include <stdio.h>
- #include <stdlib.h>
- #include <errno.h>
- #include <string.h>
- #include <sys/time.h>
- #include <sys/types.h>
- #include <sys/stat.h>
- #include <unistd.h>
- #include <fcntl.h>
- #include "npipe.h"
- #include "common.h"
- /* -------------------------------------------------------------------- */
- /* -------------------------------------------------------------------- */
- int create_named_pipe(char *file)
- {
- return mkfifo(file, O_RDWR|O_CREAT|O_NONBLOCK);
- }
- /* -------------------------------------------------------------------- */
- /* -------------------------------------------------------------------- */
- int delete_named_pipe(char *file)
- {
- return unlink(file);
- }
- /* -------------------------------------------------------------------- */
- /* Read one character from named pipe. */
- /* If no character is available block. */
- /* -------------------------------------------------------------------- */
- int block_on_named_pipe(char *file)
- {
- fd_set readfds,
- writefds,
- exceptfds;
- int nfds,
- rtval,
- fd,
- waiting,
- c,
- res;
- /* ---------------------------- */
- fd = open(file, O_RDWR|O_NONBLOCK);
- if (fd == -1)
- { return -1;
- }
- nfds = fd +1;
- FD_ZERO(&writefds);
- FD_ZERO(&readfds);
- FD_ZERO(&exceptfds);
- waiting = TRUE;
- while(waiting)
- {
- FD_SET(fd,&readfds);
- if ((rtval = select(nfds, &readfds, NULL, NULL, NULL)) != 0)
- {
- if (rtval > 0) /* Select Woken on FDs */
- {
- if (FD_ISSET(fd, &readfds))
- {
- res = read(fd, &c, 1);
- while(res != 1)
- {
- if (res == -1)
- {
- if (errno != EINTR)
- { return -1;
- }
- }
- else
- if (res == 0)
- { return -1;
- }
- res = read(fd, &c, 1);
- }
- waiting = FALSE;
- }
- }
- else
- if (rtval == -1) /* Error Return Value */
- {
- if (errno != EINTR)
- { return -1;
- }
- }
- }
- }
- close(fd);
- return 0;
- }
- /* -------------------------------------------------------------------- */
- /* Write one character to named pipe. */
- /* -------------------------------------------------------------------- */
- int write_to_named_pipe(char *file)
- {
- int fd,
- res,
- c;
- fd = open(file, O_RDWR|O_NONBLOCK);
- if (fd == -1)
- { return -1;
- }
- c = 'X';
- res = write(fd, &c, 1);
- while(res != 1)
- {
- if (res == -1)
- {
- if (errno != EINTR)
- { return -1;
- }
- }
- res = write(fd, &c, 1);
- }
- close(fd);
- return 0;
- }