Cannot use both Argv's, cannot run Move twice segmentation fault - arrays

Question

Ive been trying various ways to get my program to work. regardless of weather i try argv1 or argv2 first, the second one will segmentation fault. even if i try to print SOURCE2DEFINE or argv[2] AFTER a move() it will segmentation fault. i cannot move both files trying to run move twice will result in a segmentation fault. im assuming that it has to be something to do with pointers and allocation.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/stat.h>
#define SOURCEDEFINE argv[1]
#define SOURCE2DEFINE argv[2]
#define DESTDEFINE argv[argc - 1]
#define ARGCDEFINE argc
#define COMMANDDEFINE argv[0]
int getIndex(char, char*);
char* fileGetName(char*);
void move(char*, char*);
void copy(char*, char*);
int main(int argc, char** argv)
{
printf("Test Argc: %d\n", argc);
int lengthArray = argc-2;
printf("Test Length: %d\n", lengthArray);
printf(" command %s\n", COMMANDDEFINE);
printf("%s\n", DESTDEFINE);
if(strcmp("./copy", COMMANDDEFINE) == 0)
{
// copy(source, dest);
}
else if(strcmp("./move", COMMANDDEFINE) == 0)
{
int i = 1;
printf("Test 1: %s\n", argv[i]);
printf("Test 2: %s\n", argv[argc-1]);
move(SOURCEDEFINE, DESTDEFINE);
printf("%s Filename debug \n", SOURCE2DEFINE);
move(SOURCE2DEFINE, DESTDEFINE);
// i++;
}
return 0;
}
void moveMultiple(int argc, char** argv){
int index = 1;
while(argv[index] != NULL){
if(index < argc - 1){
move(argv[index],argv[argc - 1]);
index++;
}
}
}
void move(char *source, char* dest)
{
printf("Running Move\n");
// FILE *s = fopen(source, "r");
// FILE *s;
//FILE *s = fopen(source, "r");
strcat(dest, fileGetName(source));
int l = link(source, dest);
//if(s == NULL)
if(l)
{
printf("Error, File Not Found");
perror("Link");
fflush(stdout);
exit(1);
}
remove(source);
}
void copy(char *source, char* dest)
{
printf("Running Copy\n");
strcat(dest, fileGetName(source));
int l = link(source, dest);
//if(s == NULL)
if(l)
{
printf("Error, File Not Found");
perror("Link");
fflush(stdout);
exit(1);
}
}
char* fileGetName(char *filename)
{
int i = 0;
int length = strlen(filename);
char *catString;
int index = getIndex('/', filename);
index--;
memcpy(catString,&filename[index], length);
return catString;
}
int getIndex(char i, char *s)
{
printf("Running getIndex\n");
int index = -1;
for(int l =0; l<strlen(s); l++){
if(s[l] == i) {
index = l;
}
}
return index;
}

Answer 1

Your move method changes dest (which is really argv[i]), and overwrites the memory after it: strcat(dest, fileGetName(source));. This destroys the other parameter and probably some other things. Don't write strings into memory you don't own.