add2stdio.c

unix环境高级编程的源代码

#include    "ourhdr.h"

int
main(void)
{
    int        int1, int2;
    char    line[MAXLINE];

    while (fgets(line, MAXLINE, stdin) != NULL) {
        if (sscanf(line, "%d%d", &int1, &int2) == 2) {
            if (printf("%d\n", int1 + int2) == EOF)
                err_sys("printf error");
        } else {
            if (printf("invalid args\n") == EOF)
                err_sys("printf error");
        }
    }
    exit(0);
}