c3-5 open flag or flags of tile status flag

对一个文件状态描述符打开一个或是多个状态标志

#include "apue.h"
#include <fcntl.h>

void
set_fl(int fd,int flags) /* flags are file status flags to turn on */
    intg val

    if ((val = fcntl(fd,F_GERFL,0)) < 0)
        err_sys("fcntl error");

    val |= flags;   /* turn on flags */

    if (fcntl(fd,F_SETFL,val) < 0)
        err_sys("fcntl F_SETFL error ");
    exit(0);
}

#include "apue.h"

#include

void

set_fl(int fd,int flags) /* flags are file status flags to turn on */

intg val

if ((val = fcntl(fd,F_GERFL,0)) < 0)

err_sys("fcntl error");

val &=~flags;   /* turn off  flags */

if (fcntl(fd,F_SETFL,val) < 0)

err_sys("fcntl F_SETFL error ");

exit(0);

}