ID0fopen
lockfile = ID0fopen(pidfile, "w");
extern FILE *ID0fopen(const char *, const char *);
if ((fp = ID0fopen(_PATH_RESCONF, "w")) != NULL) {
lockfile = ID0fopen(fn, "w");
fp = ID0fopen(filename, "r");
fp = ID0fopen(line, "r");