Question

I was wondering how I could allocate (and De-Allocate) an array of char pointers (char*[64]) in C. I’ve looked around on the web for examples but they all focus on other datatypes or one dimension arrays.

Answer 1

This is answered at The C FAQ.

Here is that code adapted for char* instead of int* with some example data.

#include <stdlib.h>

#define nrows 10
#define ncolumns 64

int main(int argc, char* argv[])
{

    int i;

     //allocate 10 char*
    char **array1 = (char**)calloc(nrows,sizeof(char*));
    for(i = 0; i < nrows; i++)      
    {
        //allocate 64 chars in each row
        array1[i] = (char*)calloc(ncolumns,sizeof(char));  
        sprintf_s(array1[i],numcolumns,"foo%d",i);
    }

    for(i=0;i<nrows;i++)
        printf("%s\n",array1[i]);

     //prints:
     //  foo0
     //  foo1
     //  ..
     //  foo9
     for(i=0;i<nrows;i++)
           free(array1[i]);

     free(array1);

    return 0;
}