Re: Saving data

From:
Victor Bazarov <v.Abazarov@comAcast.net>
Newsgroups:
comp.lang.c++
Date:
Tue, 06 Apr 2010 12:28:16 -0400
Message-ID:
<hpfng1$vrd$2@news.datemas.de>
CPlusPlus wrote:

On Apr 6, 12:07 pm, CPlusPlus <aamir.a...@live.com> wrote:

typedef struct dummy // global definition
{
    char* p1;
    char* p2;

}d;

d d1;

void foobar()
{
    // allocate memory from heap
    d1.p1 = (char*)malloc(strlen("hello"+1)*sizeof(char));
    strcpy(d1.p1, "hello");

}

void main()
{
   foobar();
   printf("d1.p1 = %s\n", p1.d1); // PROBLEM: junk is printed.
   free(d1.p1);

}

I think I know why junk is printed because when foo exits, p1 data
vanishes, i.e, goes out of scope. How can I fix this?

Bare with me, I started out on writing a C++ program in MS VS2005 but
C has me figuring it out.

Thanks


typo fix: printf("d1.p1 = %s\n", d1.p1); // PROBLEM: junk is
printed.


There is no reason for printing junk. Have you tried to step through
your code in the debugger? If so, what's the value of 'd1' right after
the call to 'foobar'?

Anyway, I *strongly* recommend you to rewrite this in C++. That way we
can help.

V
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