C的FastCGI计数器

#include <fcgi_stdio.h>
int main( int argc, char *argv[] )
{
    int counter = 0;
    FILE *fp;

    char buffer[20];

    while( FCGI_Accept() >= 0 ) {
        counter = counter + 1;
        printf( "Content-Type: text/plain\n\n" );
        printf( "%d",counter );
        if (counter >= 100){
           sprintf(buffer, "%d", counter);
           fp =fopen("/tmp/counter.txt","a");
           fputs(buffer, fp);
           fputs("\n", fp);
           fclose(fp);
           counter = 0;
        }
    }
    return 0;
}