• C

Define pointers

How can I define three character pointers a, b, and c.
They are not arrays, and not initialized.
Make a point to "Hello", and b point to "World".
Concatenate these tow strings into c.
(Make sure c has enough memory allocated)
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#include <string.h>
char *a,*b,*c;
a = "Hello";
b = "World";
c = (char *)malloc(strlen(a)+strlen(b)+1);

Ozo, that should have been an answer.
The answer was a comment eh? :)

BTW, it's good programming practice to free up allocated memory after you're done with it :)

ie. free(c);

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And since you don't want to leave c pointing to unallocated memory:

c = 0;

Of course, in C, you don't need the (char*) cast - and it _can_ be dangerouse to leave it there.

Ozo, pls Answer the question.
/* Answer for rbr: */
#ifdef _SVID
#include <malloc.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
char *a,*b,*c;
a = "Hello";
b = "World";
c = malloc(strlen(a)+1+strlen(b)+1);
sprintf(c,"%s %s",a,b);
/* we could free(c) here, but I'd prefer to wait till after it's been used */

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Since the subject seems to be new to pointers, it might be prudent to add that you should _not_ try to modify *a or *b (including a[whatever] and b[whatever]) since that would be trying to modify parts of the executable in run-time, which will, in turn, cause a GPF or a segfault, depending on your operating system.
It looks like luonght was less interested in geting this answered than rbr was.
luonght, if you don't like the answer, please reject it, if you do, please grade it.
char *a,*b,*c;
a = strdup("Hello"); /* if you want *a to be modifiable */
b = strdup("World");
c = (char *)malloc(strlen(a)+strlen(b)+1);
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