CS456 - Systems Programming Spring 2026

Displaying ./code/h2ex/extras.h

/*

This custom header file has functions written by me for use in other programs

To use in your source code add this line: #include "extras.h"


*/

//needed header files for functions
#include <sys/stat.h>

//definining stat structure for functions that use the stat structure
struct stat st;

//this function gets the size of a file
int get_fdSize(int fd){

	//fstat is a fuction that gets the status of a file(from a file descriptor) and stores it in st.
	fstat(fd, &st);
	return st.st_size; //returning the value in the size field

}

//gets the file opermissions
int get_fdPerms(int fd){

	fstat(fd, &st);

	//binary AND'ing the octal value 0777 with the mode field to get the permissions
	//then returning that value
	return st.st_mode & 0777;  

}