implement Env; ## Copyright © 2000 Vita Nuova Limited.  All rights reserved.# include "sys.m";	sys: Sys;include "draw.m";include "bufio.m";include "readdir.m";include "env.m"; ENVDIR : con "/env/"; setenv(var: string, val: string): int{	init();	if (var == nil || !nameok(var)) {		sys->werrstr("bad variable name");		return -1;	}	if (val == nil) {		sys->remove(ENVDIR+var);		return 0;	}	fd := sys->create(ENVDIR+var, Sys->OWRITE, 8r600);	if (fd == nil)		return -1;	valb := array of byte val;	if (sys->write(fd, valb, len valb) != len valb)		return -1;	return 0;} getenv(var: string): string{	init();	if (var == nil || !nameok(var))		return nil;	fd := sys->open(ENVDIR+var, Sys->OREAD);	if (fd == nil)		return nil;	(ok, stat) := sys->fstat(fd);	if (ok == -1)		return nil;	buf := array[int stat.length] of byte;	n := sys->read(fd, buf, len buf);	if (n < 0)		return nil;	return string buf[0:n];} getall(): list of (string, string){	readdir := load Readdir Readdir->PATH;	if (readdir == nil)		return nil;	(a, nil) := readdir->init(ENVDIR,			Readdir->NONE | Readdir->COMPACT | Readdir->DESCENDING);	vl: list of (string, string);	for (i := 0; i < len a; i++)		vl = (a[i].name, getenv(a[i].name)) :: vl;	return vl;} # clone the current environmentclone(): int{	init();	return sys->pctl(sys->FORKENV, nil);} new(): int{	init();	return sys->pctl(sys->NEWENV, nil);} init(){	if (sys == nil)		sys = load Sys Sys->PATH;} nameok(var: string): int{	for(i:=0; i<len var; i++) 		if (var[i] == '/') return 0;	return 1;}