C code that will open a file and print the contents to the terminal.

#include <stdio.h>
 
#define MEM "/proc/diskstats"
 
int main (void) {
 
	FILE *g;
	char Meminfo[40];
	g = fopen(MEM, "r");
	if(!g) {
		printf ("Sorry, I cannot open: %s.\n", MEM);
	} else {
		while (feof(g) != 1) {
			fgets(Meminfo, 2, g);
			printf("%s", Meminfo );
		}
		fflush(stdout);
	}
	fclose(g);
}

#include <stdlib.h>
#include <stdio.h>
 
int main(void) {
	FILE *f;
	char buf[256];
 
	f = fopen("logfile", "a+");
	if(f) {
		fprintf(f, "This is appended to the file.\n");
	}
	fclose(f);
	return 0;
}

	f = fopen("logfile", "w+");