ossc/software/sys_controller_bsp/HAL/src/alt_fd_unlock.c

/******************************************************************************
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* License Agreement                                                           *
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* Copyright (c) 2004 Altera Corporation, San Jose, California, USA.           *
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#include <errno.h>

#include "priv/alt_file.h"

/*
 * alt_fd_unlock() is the inverse of alt_fd_lock(). It is called as a 
 * consequence of a TIOCNXCL ioctl request, e.g:
 *
 * ioctl (fd, TIOCNXCL, NULL);
 *
 * It enables multiple file descriptors to exist for the same device. This
 * is normally the case, but it may have been disabled by a previous call to
 * alt_fd_lock().
 *
 * Return zero on sucess, and a negative value on failure.
 *
 * The current implementation always succeeds.
 */

int alt_fd_unlock (alt_fd* fd)
{
  fd->fd_flags &= ~ALT_FD_EXCL;
  return 0;
}