Download the source code here:
Download a sample .ini file:

Usage example:

int main(void)
{
// an example of how to call the functions...
char *value = readFromINI(INI_FILENAME, "Section2", "Entry2");
printf("returned value from readFromINI: %s\n", value);
free(value);
writeToINI(INI_FILENAME, "Section2", "Entry2", "I've changed this value! Weehee!!!");
getchar ();
return 0;
}