Small tweaks

Lots of new code imported.

src/lib9/getenv.c

@@ -22,6 +22,5 @@ p9putenv(char *s, char *v)
 	if(t == nil)
 		return -1;
 	putenv(t);
-	free(t);
 	return 0;
 }

src/lib9/mkfile

@@ -107,6 +107,8 @@ LIB9OFILES=\
 	getuser.$O\
 	getwd.$O\
 	jmp.$O\
+	lrand.$O\
+	lnrand.$O\
 	lock.$O\
 	main.$O\
 	malloc.$O\
@@ -119,6 +121,7 @@ LIB9OFILES=\
 	nrand.$O\
 	nulldir.$O\
 	open.$O\
+	opentemp.$O\
 	pipe.$O\
 	post9p.$O\
 	postnote.$O\

src/lib9/pipe.c

@@ -3,6 +3,11 @@
 #include <libc.h>
 #include <sys/socket.h>
 
+/*
+ * We use socketpair to get a two-way pipe.
+ * The pipe still doesn't preserve message boundaries.
+ * Worse, it cannot be reopened via /dev/fd/NNN on Linux.
+ */
 int
 p9pipe(int fd[2])
 {