and remove duplicate declaration of perror.
extern PROTO(int, bcmp,(char *, char *, int));
extern PROTO(void, bzero,(char *, int));
extern char * strchr();
-extern PROTO(void, perror,(char *));
+extern PROTO(void, perror,(CONST char *));
extern char *getenv();
extern char *memchr();
extern char *strrchr();
void free();
char *malloc();
char *realloc();
-PROTO (void, perror, (char *s));
extern char *strrchr();
extern char *ctime();
extern int _flsbuf();