strace跟踪系统调用

/*
* strace跟踪系统调用
* gcc strace_test.c -o strace_test
* ./strace_test
* ps ax | grep strace_test
* 4338 pts/0    S+     0:00 ./strace_test
* strace -p 4338
*/
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>

int main()
{
char buf[1024];
int cnt,i;
cnt=read(STDIN_FILENO,buf,1024);
for(i=0;i<cnt;++i)putchar(buf[i]);
putchar('\n');
return 0;
}