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Date: Mon, 13 May 2002 19:06:57 +0200 (MEST)
From: Paul Everlund <tdv94ped@cs.umu.se>
To: <freebsd-questions@freebsd.org>
Subject: C malloc question
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Hi all!

I have a question regarding malloc and returning arrays in C.

The following C program is an example.

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

static char *init()
{
  char *str;
  int i;

  str = (char *)malloc(sizeof(char), 128);
  for(i = 0; i < 127; i++)
    str[i] = "A";
  str[i] = '\0';
  return str;
}

int main()
{
  int i;

  for(i = 0; i < 500000; i++)
    init();
  printf("%s\n", init());
  return 0;
}

This program takes up a lot of malloc'ed memory after a while,
so how do one return arrays and free memory in the main function
everytime the array have been used? I would like to not use fix-
ed size arrays, as the real function should be general enough
to handle all kind of array sizes.

As the size is known in the main function, I guess I could send
in a buffer to get the data, as in init(char *buf), but I would
like to avoid this.

What is the best solution for this problem?

Thanks a lot in advance!

Best regards,
Paul


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