Thread: Strange Character in Programs Output:

Okay, I was trying to make a simple program to list all the files with a certain termination in a folder of my system (Slackware Linux 9) following the intructions of the book "Linux Application Development by Michael K. Johnson and Erik W. Troan" I got the following piece of code:

Code:

#include<stdlib.h>
#include<sys/wait.h>

int main(){
	int result;
	
	result = system("exec ls *.c");
	
	if (!WIFEXITED(result)){
		printf("Abnormal termination\n");}
		else 	
			printf("%d",result);
	
	exit(0);
}

Okay result is storing perfectly all the names of *.c files but I'm also recieving a zero in the final output here is a sample of the output:
imanewbie@blah:~/Projects/Junk Code$ ./listsc
array.c dinamicstack.c hashtable.c queue.c struct2.c test.c
child.c doublepointer.c linkedlist.c random.c struct.c tripointer.c
conta.c hamash.c listsc.c senha.c swapbytes.c
0

I would like to know if someone can explain me what is this 0 cause the book doesn't mention is and I don't even know what to search for in the internet. Thanks a lot.

Originally Posted by Salem

You mean the 0 printed by this

printf("%d",result);

Or some other zero?

Yes the 0 from the printf("%d",result)

Originally Posted by Salem

Oh, you mean why is result 0

Well that's the return result of the system() call.
Which MAY in turn be the exit status of the program you tried to run.

Hum... I think you are right, system() returns 0 if succesfull, well there would be a way to me remove this 0, well not remove but hide it?

Originally Posted by chrismiceli

What would you like it to print?

I would like to print all the .c files but without the 0, I'm using it to list mp3's in fact just using .c to make a more simple example.