我刚开始在ubuntu（9.04）下用gcc编写ansi c。我得到以下错误消息：

错误消息：

main.c:6: error: expected identifier or ‘(’ before ‘/’ token
In file included from /usr/include/stdio.h:75,
                 from main.c:9:
/usr/include/libio.h:332: error: expected specifier-qualifier-list before ‘size_t’
/usr/include/libio.h:364: error: expected declaration specifiers or ‘...’ before ‘size_t’
/usr/include/libio.h:373: error: expected declaration specifiers or ‘...’ before ‘size_t’
/usr/include/libio.h:493: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘_IO_sgetn’
In file included from main.c:9:
/usr/include/stdio.h:314: error: expected declaration specifiers or ‘...’ before ‘size_t’
/usr/include/stdio.h:682: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘fread’
/usr/include/stdio.h:688: error: expected ‘=’, ‘,’, ‘;’, ‘asm’ or ‘__attribute__’ before ‘fwrite’
main.c:12: error: expected identifier or ‘(’ before ‘/’ token

我认为这是一个非常简单的问题，也许是在ubuntu或gcc的配置中。我也是linux下编程的新手。我在谷歌上寻求帮助，并通过tutorial，但找不到答案。谢谢！

代码：

/* cheat with the preprocessor to skip over missing lines to attempt
   to duplicate the circumstance of the original code */
#line 9
// #include <some_random_header.h>
#include <stdio.h>
#include <math.h>    
int main(int argc, char **argv)
    {
     printf("TestOutput\n");

     return (0);
    }

命令：

~/Documents/projects/Trials$ gcc -Wall -ansi  main.c