i want to write a simple programme with the function malloc on a function..
i want to write a function where i will have a table MAX(define the MAX) with strings and read it
later i want to save every string on the table in that way that i don't have loose on my mamory (realloc)
i have write a code but i'm confuse with the 2 dimension table with arrow, can anyone help me....?
thanks

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 3

char *func();
char *func()
{

    char *temp[MAX][100],*ptr;
    int i,pin2[MAX];

    for (i=0;i<MAX;i++)
    {
        *(temp+1)=malloc(100*sizeof(char));
        gets(*(temp+i));
        pin2[i]=strlen(*(temp+i))+1;
    }

    for (i=0;i<MAX;i++)
    {
        *(temp+i)=realloc(*(temp+i),pin2[i]*sizeof(char));

    }
    ptr=temp;
    return ptr;


}


main()
{
    char *str;
    int i;

    str=func();

    for (i=0;i<MAX;i++)
    puts(*(str+i));
}

Recommended Answers

All 2 Replies

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define MAX 3

char **func();
char **func()
{

    char **temp,**ptr;
    int i,pin2[MAX];

    for (i=0;i<MAX;i++)
    {
        *(temp+sizeof(char)*100*i)=malloc(100*sizeof(char));
        gets(*(temp+sizeof(char)*100*i));
        pin2[i]=strlen(*(temp+sizeof(char)*100*i))+1;
    }

    for (i=0;i<MAX;i++)
    {
        *(temp+sizeof(char)*100*i)=realloc(*(temp+sizeof(char)*100*i),pin2[i]*sizeof(char));

    }
    ptr=temp;
    return ptr;


}


main()
{
    char **str;
    int i,j;

    str=func();
/*
    for (i=0;i<MAX;i++)
    puts(str[i]);
*/
    for (i=0;i<MAX;i++)
    {
        for (j=0;j<5;j++)
        {
            printf("%c",str[i][j]);
        }
    }

}

this one is better but with still errors

You're vastly overcomplicating trivial stuff and ignoring important stuff. Compare and contrast your code with this:

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

#define MAX 3
#define LEN 100

char **func(void)
{
    char **ptr = malloc(MAX * sizeof *ptr);

    /* Always check malloc for failure */
    if (ptr) {
        size_t i;

        for (i = 0; i < MAX; i++) {
            ptr[i] = malloc(LEN * sizeof *ptr[i]);

            /* Leave a null pointer if malloc fails */
            if (ptr[i]) {
                /* Always check input for failure too */
                if (fgets(ptr[i], LEN, stdin)) {
                    /* Try to shrink wrap the memory to the string length */
                    char *temp = realloc(ptr[i], strlen(ptr[i]) + 1);

                    /* Take care not to lose the original pointer on failure */
                    if (temp)
                        ptr[i] = temp;
                }
            }
        }
    }

    return ptr;
}

int main(void)
{
    char **str = func();
    size_t i;

    for (i = 0; i < MAX; i++) {
        if (str[i])
            puts(str[i]);
    }

    /* Don't forget to release your allocated memory */
    for (i = 0; i < MAX; ++i)
        free(str[i]);
    free(str);

    return 0;
}

On top of actually working, my code also checks for error cases and handles them gracefully. Your code would probably crash and burn under those same cases.

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