Pointer initialization doubt

Posted by Jestin Joy on Programmers See other posts from Programmers or by Jestin Joy
Published on 2011-01-06T03:47:59Z Indexed on 2011/01/06 3:58 UTC
Read the original article Hit count: 362

Filed under:

c

|

pointers

We could initialize a character pointer like this in C.

char *c="test";

Where c points to the first character(t).

But when I gave code like below. It gives segmentation fault.

#include<stdio.h>
#include<stdlib.h>
main()
{

 int *i;
 *i=0;
 printf("%d",*i);
}

But when I give

#include<stdio.h>
#include<stdlib.h>
main()
{
 int *i;
 i=(int *)malloc(2);
 *i=0;
 printf("%d",*i);
}

It works( gives output 0).

Also when I give malloc(0), It also works( gives output 0).

Please tell what is happening

Pointer initialization doubt

Posted by Jestin Joy on Stack Overflow See other posts from Stack Overflow or by Jestin Joy
Published on 2011-01-06T04:29:46Z Indexed on 2011/01/06 4:54 UTC
Read the original article Hit count: 362

Filed under:

linux

|

pointers

|

gcc

|

malloc

We could initialize a character pointer like this in C.

char *c="test";

Where c points to the first character(t).

But when I gave code like below. It gives segmentation fault.

#include<stdio.h>
#include<stdlib.h>
main()
{

    int *i=0;
    printf("%d",*i);
}

Also when I give

#include<stdio.h>
#include<stdlib.h>
main()
{
    int *i;
    i=(int *)malloc(2);
    printf("%d",*i);
}

It worked(gave output 0).

When I gave malloc(0), it worked(gave output 0).

Please tell what is happening

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