Extra characters added to beginning of string?

Question

I have two extra characters being added to the beginning of my string and I can't seem to find out why. The characters don't even appear in the code. I'm at a loss here. This is my code:

#include <stdlib.h>
#include <stdio.h>
#include <string.h>

char *chars;

char* vector(char input, char *newlist);

int main(){

    char *input, *out = "Input: ";

    printf("Enter characters: ");                   
    while(1){
        char i = getchar();                         //get input
        if(i == '\n'){
            break;                                  //detect a return key
        } else{
            input = vector(i, input);               //call vector
        }
    }

    char * print = (char *)malloc(1 + strlen(input) + strlen(out));
    strcpy(print, out);                             //concat the strings
    strcat(print, input);

    printf("\n%s", print);                          //print array

    free(print);
    free(input);
    free(chars);

    return 0;                                       //exit
}

char* vector(char in, char *newlist){

    int length = strlen(newlist);                   //determine length of newlist(input)

    chars = (char*)calloc(length+2, sizeof(char));  //allocate more memory
    strcpy(chars, newlist);                         //copy the array to chars
    chars[length] = in;                             //appened new character
    chars[length + 1] = '\0';                       //append end character

    return chars;
}

For some reason, the code produces this:

Enter characters: gggg

Input: PEgggg

When it should be producing this:

Enter characters: gggg

Input: gggg

Answer 1

All the points @MikeCat are said are correct, just to add that the memory allocated by calloc is not freed which leads to a memory leak. You can free it as said by @M.M in a comment, but for next time, to avoid memory leaks, you can use valgrind:

Let's take your program, as hash.c. Got to the command line and compile it, for eg :

gcc hash.c -Wall

If your program compiles successfully, an executable or out file will appear. As we have not specified the name of the executable, it's default name will be a.out. So let's run it with valgrind:

valgrind -- leak-check=full ./a.out

This will run executable, along with valgrind, and if there is a memory leak, it will show it when the executable ends.

---

If you do not have valgrind installed, you can install it from here.