求解释 setbuf fflush 最好有案例 不要百度百科的

12月30日

#include <stdio.h>
main()
{char outbuf[5]="asdw";
setbuf(stdout,outbuf);
puts("This is a test of buffered output.");
puts("This output will go into outbuf");
puts("and won't appear until the buffer");
puts("fills up or we flush the stream.\n");
puts(outbuf);
fflush(stdout);
return 0;
}