c语言不是很会，但是要用到这次，请教fprintf()方法的参数的意义，以及怎样向文件输出无符号长整型用那个格式符

c语言不是很会，但是要用到这次，请问fprintf()方法的参数的意义，以及怎样向文件输出无符号长整型用那个格式符
如题，谢谢！

------解决方案--------------------
格式化输出到一个流，比如文件流

// crt_fprintf.c
/* This program uses fprintf to format various
* data and print it to the file named FPRINTF.OUT. It
* then displays FPRINTF.OUT on the screen using the system
* function to invoke the operating-system TYPE command.
*/

#include <stdio.h>
#include <process.h>

FILE *stream;

int main( void )
{
int i = 10;
double fp = 1.5;
char s[] = "this is a string ";
char c = '\n ';

fopen_s( &stream, "fprintf.out ", "w " );
fprintf( stream, "%s%c ", s, c );
fprintf( stream, "%d\n ", i );
fprintf( stream, "%f\n ", fp );
fclose( stream );
system( "type fprintf.out " );
}
------解决方案--------------------
%lu