Segfault (core dump) - cannot get lldb to run

Question

I am trying to write a program that extracts information from proc. Right now I am trying to get the processor type from cpuinfo. My code compiles, but I am getting a segfault (core dump). I cannot get lldb to run to debug. Here is my code:

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <string.h>


char cpuinfo()
{
    char element[400];
    FILE* fp;
    fp = fopen("/proc/cpuinfo", "r");
    int token_count = 0;

    if (fgets(element, 400, fp) != NULL)
    {
       char *token;
       token = strtok(element, "\n");
       printf("%s\n", token[4]);
    }


    fclose(fp);
    return(0);
}

int main(int argc, char *argv[])
{
    printf("Hello world\n");
    cpuinfo();
}

Answer 1

You fail to perform any bounds validation. Will token have an element '4'?

printf("%s\n", token[4]);

Try

for ( char *token = strtok( element , "\n" ); token != NULL; token = strtok( NULL, "\n" ) )
{
  puts( token );
}