是否可以使用 tee 捕获标准输入？

Question

当我将我的程序通过管道传输到 tee 函数时，是否可以捕获来自 scanf(...) 的输入？例如，我有这个程序：

int main() {
    int d;
    printf("Enter a number: ");
    scanf("%d", &d);
    printf("Your number is %d\n", d);
}

当我执行命令./a.out | tee out.txt时，我看到

7
Enter a number: Your number is 7

而out.txt是：

Enter a number: Your number is 7

如何让终端和输出文件同时显示：

Enter a number: 7
Your number is 7

Answer 1

如果要捕获终端会话，请使用 script。例如：

$ cat a.c
#include <stdio.h>
int
main(void)
{
        int d;
        printf("Enter a number: ");
        if( scanf("%d", &d) == 1 ){;
                printf("Your number is %d\n", d);
        }
        return 0;
}
$ gcc a.c
$ rm -f foo
$ SHELL=/bin/sh script foo
Script started, output file is foo
sh-3.2$ ./a.out
Enter a number: 5
Your number is 5
sh-3.2$ exit
exit

Script done, output file is foo
$ cat foo
Script started on Wed Apr  7 16:48:03 2021
sh-3.2$ ./a.out
Enter a number: 5
Your number is 5
sh-3.2$ exit
exit

Script done on Wed Apr  7 16:48:13 2021

是否可以使用 tee 捕获标准输入？

Is it possible to capture standard input with tee?

c

pipe

stdin

tee