int2str.c

#include <stdio.h>
#include <string.h>
#include <math.h>

void int2str(long, char *);

int main(int argc, char *argv[])
{
  long i = 12345;
  char str[] = "00000\0";
  int2str(i, str);
  puts(str);
  return 0;
}

void int2str(long n, char *str)
{
  int len = strlen(str);
  int i;
  for( i = 0; i < len; i++ )
    {
      long mask = pow(10, i+1);
      int a = (n % mask) / pow(10, i);
      char c = (char)(a + (unsigned short)'0');
      str[len-i-1] = c;
    }
}