printf("%s", str) vs. printf(str)

Created: Fang lungang 03-08-2007Modified: Fang lungang 03-08-2007 21:35>

从 The C Programming Language 2nd 看到的 printf 一个需要注意的细节：即使被打印的本身就只有一个字符串，最好也别直接打印，而要用格式符 %s。其它格式输出的函数应该也类似。

#include <stdio.h>

int main()
{
        char* str= "a string with % may not workn";
        printf ("%s", str);
        printf (str);
        return 0;
}

[/home/lungangfang/tmp]gcc --version
gcc (GCC) 3.2.3 20030502 (Red Hat Linux 3.2.3-20)
Copyright (C) 2002 Free Software Foundation, Inc.
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

[/home/lungangfang/tmp]./a.out
a string with % may not work
a string with Successay not work
[/home/lungangfang/tmp]