Why am I receiving segmentation fault (core dumped)?

This program was created to log the counter every 5 seconds. The while loop needs to be running while the daemon process is running in the background and logging the counter.

The error I’m receiving is: Segmentation fault (core dumped). the terminal ask to input a number, when I input the number I receive the error.

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
int main(int argc, char* argv[])
{
int clos =0;
int count=0;

I think the while loop below may be in the wrong place.

while(clos !=1){
    
    printf("Type: ");
    scanf("%d",clos);
    if (clos !=1){
        count = clos;
    }
}
    
    
FILE *fp= NULL;
pid_t process_id = 0;
pid_t sid = 0;
// Create child process
process_id = fork();
// Indication of fork() failure
if (process_id < 0)
{
printf("fork failed!n");
// Return failure in exit status
exit(1);
}
// PARENT PROCESS. Need to kill it.
if (process_id > 0)
{
printf("process_id of child process %d n", process_id);
// return success in exit status
exit(0);
}
//unmask the file mode
umask(0);
//set new session
sid = setsid();
if(sid < 0)
{
// Return failure
exit(1);
}
// Change the current working directory to root.
chdir(".");
// Close stdin. stdout and stderr

// Open a log file in write mode.
fp = fopen ("Log.txt", "w+");
while (1)
{
//Dont block context switches, let the process sleep for some time
sleep(1);
fprintf(fp, "Logging info...n");
fprintf(fp, counter);
fflush(fp);
// Implement and call some function that does core work for this daemon.
    
}


fclose(fp);
return (0);
}

Answer

Like kjohri said, you need to pass a pointer to clos in the scanf function

Add an & symbol

scanf("%d", &clos);
            ^

Also it looks like you named the variable count, but in the function you wrote counter. Instead write:

fprintf(fp, "%d", count);

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Answer