should i put gets () before scanf()?

harrypotter

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdio.h>
main ()
{
char name[8];
char buf[1024];
int a,b;
printf ("input content:");
gets (buf);
printf ("input file name:");
scanf ("%s", name);
a = open (name, O_WRONLY);
write (a, buf,strlen(buf));
close (a);
}
a very funny thing:in the codes above,if i put scanf before gets(),just like:
.............
printf ("input file name:");
scanf ("%s", name);
printf ("input content:");
gets (buf);
............
after i compile it,the program will be quit automatically
who can tell me why?
sorry,there are some bugs with my xsim,so i had to type all in Eng

ykwj121

是因为scanf和gets的字符结束标志的原因。
scanf先接受字符，它遇到最后一个输入的回车并不处理，直接返回它已经得到的字符串，而gets会直接得到那个scanf没有处理到的回车。

你可以做个测试，scanf读到空格也是会对回车一样的。而gets显然可以读到scanf时候输入的空格及接下来的字符。并将其存到文件里面。

假设你调换了两句的位置，先scanf然后gets
你按如下输入
[root@abcdefg test]# touch hi
[root@abcdefg test]# ./a.out
input file name:hi hihihi
input content:
[root@abcdefg test]#
[root@abcdefg test]# cat hi
hihihihi[root@abcdefg test]#

harrypotter

9494,谢谢