App keeps crashing with malloc issue objective c and c - objective-c

Question

Question- I want to be able to run my c code over and over again however after the first execution of it in my objective c it crashes and I receive an error in xcode "Thread 1 EXC_BAD_ACESSS (code=1, address=0x0)". It's really strange because the first time I run it works then any time after that it dies on me. Any help would be greatly appreciated.
Here is my c code
funcc.c
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
#define BUFLEN 1024
#define MYFREE(x) free(x); x = NULL;
char const *ipcc;
char *statuss;
char *both_words;
char *s1;
char *s2;
char *results;
void concat()
{
**// THIS IS THE LINE I RECIEVE THE EXC_BAD_ACCESS ERROR/////************** results
results = malloc(strlen(s1)+strlen(s2)+1);
strcpy(results, s1);
strcat(results, s2);
both_words = results;
return;
}
char* P(const char *ipAddr)
{
int pipe_arr[2];
char buf[BUFLEN];
pipe(pipe_arr);
if(fork() == 0)
{
dup2(pipe_arr[1], STDOUT_FILENO);
execl("/sbin/ping", "ping", "-c 1", ipAddr, (char*)NULL);
}
else //parent
{
wait(NULL);
read(pipe_arr[0], buf, BUFLEN);
char *xxx = deblank(buf);
char *input = xxx;
char delimiter[] = " ";
char *i, *j, *remainder, *context;
int inputLength = strlen(input);
char *inputCopy = (char*) calloc(inputLength + 1, sizeof(char));
strncpy(inputCopy, input, inputLength);
i = strtok_r (NULL, delimiter, &context);
j = strtok_r (NULL, delimiter, &context);
remainder = context;
s1 = i;
s2 = j;
concat();
char *sx = search(both_words);
//getchar();
}
close(pipe_arr[0]);
close(pipe_arr[1]);
return both_words;
}
void ConnectionMain(){
char *val = P(ipcc);
printf("%s\n", val);
char *valb = "0packets";
if(strcmp(val, valb) == 0)
{
printf("%s\n", "noconnection");
statuss = "noconnection";
//free(concat);
//return "noconneciton";
}
else
{
printf("%s\n", "connected");
statuss = "connected";
//free(concat);
//return "connected";
}
s1 = NULL;
s2 = NULL;
results = NULL;
both_words = NULL;
ipcc = NULL;
}
funcc.h
#include <stdio.h>
#include <sys/wait.h>
#include <unistd.h>
#include <string.h>
#include <stdlib.h>
#include <stdbool.h>
extern const char *ipcc;
extern char *statuss;
//const char *TestConnection(const char *ip);
void ConnectionMain();
Here is my objective c code
ViewCtrl.m
- (void)checkconnection
{
ConnectionMain();
//const char *ipc = [ip UTF8String];
//TestConnection(ipc);
char *statuss1 = "noconnection";
NSString* xx = [NSString stringWithUTF8String:statuss];
//printf("%s\n", statuss);
if(strcmp(statuss, statuss1) == 0)
{
_ip_label.stringValue = #"No Connection";
//I TRIED SETTING THESE BACK TO NULL BUT STILL NO LUCK
// I ALSO TRIED FREE(CONCAT) STILL NO LUCK
ipcc = NULL;
statuss = NULL;
statuss1 = NULL;
}
else
{
//I TRIED SETTING THESE BACK TO NULL BUT STILL NO LUCK
// I ALSO TRIED FREE(CONCAT) STILL NO LUCK
_ip_label.stringValue = #"Connection Success";
ipcc = NULL;
statuss = NULL;
statuss1 = NULL;
}
}
- (IBAction)ipButtonClicked:(id)sender {
//THIS IS WHERE I EXECUTE MY C CODE///////*********
NSString *ip_text = _ip_text_box.stringValue;
const char *ipxx = [ip_text cStringUsingEncoding:NSUTF8StringEncoding];
ipcc = ipxx;
[self checkconnection];
}