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Full Discussion: a problem about malloc()
Top Forums Programming a problem about malloc() Post 25798 by chenhao_no1 on Monday 5th of August 2002 10:58:45 PM
Old 08-05-2002
1 .I found the answer .
2 .First , I write another programe .
#include <stdio.h>
#include <string.h>

int main(void)
{
char *p;

p = (char *) malloc(100);

strcpy(p, "asdfasdf");

return 0;
}

It works correctly .
3 . Why ? The point is that :
p is a local varible , when we call do_it(p) , the OS pass a copy of p to child function .Though we malloc memory to p in child function ,the p variable in main function is not changed .
 

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explain_malloc_or_die(3)				     Library Functions Manual					  explain_malloc_or_die(3)

NAME
explain_malloc_or_die - Allocate and free dynamic memory and report errors SYNOPSIS
#include <libexplain/malloc.h> void *explain_malloc_or_die(size_t size); DESCRIPTION
The explain_malloc_or_die function is used to call the malloc(3) system call. On failure an explanation will be printed to stderr, obtained from explain_malloc(3), and then the process terminates by calling exit(EXIT_FAILURE). This function is intended to be used in a fashion similar to the following example: void *result = explain_malloc_or_die(size); size The size, exactly as to be passed to the malloc(3) system call. Returns: This function only returns on success. On failure, prints an explanation and exits. SEE ALSO
malloc(3) Allocate and free dynamic memory explain_malloc(3) explain malloc(3) errors exit(2) terminate the calling process COPYRIGHT
libexplain version 0.52 Copyright (C) 2009 Peter Miller explain_malloc_or_die(3)
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