split string function

hello. i am trying to make a split function that takes in a string and a delimiter, and returns a array of strings that have been separated by the delimiter.

here is my code so far:

Code:

---

char  * split(char string[], char * sep){
        // char str[] = &string;
        char * pch;
        char * out[3];
        int i=0;
        printf ("h1\n");
        pch = strtok (string," ,");
        printf ("h2\n");
        while (pch != NULL)
        {
                printf ("\"%s\"\n",pch);
                out[i] = pch;
                i++;
                if(pch != NULL) pch = strtok (NULL, " ,");
        }
        //out[i] = '\0';
        printf("h3 %s\n",out[0]);
        return out;
}

int main(){
       
        printf("start\n");
        char * out = split(str, " ,");
        printf("end\n");
        printf ("out 1: %s\n",out[0]); // segmentation fault happens here
        printf ("out 2: %s\n",out[1]);
        printf ("out 3: %s\n",out[2]);
        return 0;
}

---

the input i used is: "this, is, crazy"

i get a segmentation fault after the printf of "end"

listen to your compilers warnings.
Kurt

something to the effect of this:

Code:

---

database.c: In function ‘split’:
database.c:47: warning: return from incompatible pointer type
database.c:47: warning: function returns address of local variable
database.c: In function ‘test’:
database.c:70: error: incompatible types in assignment
database.c: In function ‘start_database’:
database.c:87: warning: excess elements in scalar initializer
database.c:87: warning: (near initialization for ‘row’)

---

is this file named 'database.c'? if so then post the full code.
it would be helpful to us if you commented or somehow let us know what lines are #47, 70, and 87.

edit: it looks like your trying to do something with the variable 'out'. however it isnt initialized.

Code:

---

char * out[3];

---

is a pointer to an array of three chars.

It's not that simple what you are trying to do. Right now I don't have the nerve to try to explain how to do that.
try this code.

Code:

---

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

char  ** split(char string[], int * num, char * sep) {
        char * pch;
        char ** out = 0;
        int i = 0;
        pch = strtok (string, sep );
     
        while (pch != 0 ) {
                out = realloc(out, (  i + 1 ) * sizeof( char * ));
                out[i] = malloc( strlen(pch ) + 1 );
                strcpy( out[i], pch );
                ++i;
                pch = strtok (NULL, sep);
        }
        *num = i;
        return out;
}


int main() {
    char str[255] = "one, two, tree, four,five  six";
    int num = 0;
    int i = 0;
    char ** tokens = split( str, &num, " ,");
    for( i = 0; i < num; ++i )
      printf("&#37;s\n", tokens[i] );

    for( i = 0; i < num; ++i )
      free( tokens[i] );

    free(tokens);
}

---

Feel free to ask how it works.
Kurt

EDIT: proper error checking needs to be added.

thank you ZuK this works.
i love the versitilty of c.. but i have worked with python for so long, i forgot to appreciate c.

i would like to know how this works..
like the functions
realloc and free

realloc
free