6.4.3 获得当前终端名称

    
//p6.1.c 获得标准输入、输出和错误输出的终端名称
#include <stdio.h>
#include <unistd.h>
int main(int argc,char* argv[]){
//下面3个字符指针分别用来保存标准输入、标准输出和
//标准错误输出的终端名
char* tty_out_name;
char* tty_in_name;
char* tty_err_name;
//调用ttyname函数来获得终端名称，如果返回结果为NULL，表示
//调用失败，输出错误信息
if((tty_out_name=ttyname(STDOUT_FILENO))==NULL){
perror("Cannot get tty name");
return 1;
}
//打印输出获得的终端名称
printf("STDOUT_FILENO tty name is :%s\n",tty_out_name);
if((tty_in_name=ttyname(STDIN_FILENO))==NULL){
perror("Cannot get tty name");
return 1;
}
printf("STDIN_FILENO tty name is :%s\n",tty_in_name);
if((tty_err_name=ttyname(STDERR_FILENO))==NULL){
perror("Cannot get tty name");
return 1;
}
printf("STDERR_FILENO tty name is :%s\n",tty_err_name);
return 0;
}

   [program@localhost charter6]$ gcc -o p6.1 p6.1.c 
[program@localhost charter6]$ ./p6.1 
STDOUT_FILENO tty name is :/dev/pts/6
STDIN_FILENO tty name is :/dev/pts/6
STDERR_FILENO tty name is :/dev/pts/6
[program@localhost charter6]$ who
root     pts/3        2007-01-07 21:25 (:0.0)
program  pts/6        2007-01-07 22:57 (192.168.106.1)
[program@localhost charter6]$