config_dir = (char *)XP_CALLOC(len, sizeof(char));
config_dir = (char *)XP_CALLOC((unsigned int)len, sizeof(char));
char *fe_GetConfigDir(void) {  char *home = getenv("HOME");  if (home) {    char *config_dir;    int len = strlen(home);    len += strlen("/") + strlen(MOZ_USER_DIR) + 1;    config_dir = (char *)XP_CALLOC(len, sizeof(char));    /* we really should use XP_STRN*_SAFE but this is MODULAR_NETLIB */    XP_STRCPY(config_dir, home);    XP_STRCAT(config_dir, "/");    XP_STRCAT(config_dir, MOZ_USER_DIR);     return config_dir;  }    return strdup("/tmp");}