[9fans] manual suggestions and upas/fs bug

[David Swasey <swasey@cs.cmu.edu>]

Hi,

The malloc(2) page says:

	The call realloc(0, size) means the same as `malloc(size)'.
	Further, the call realloc(ptr, 0) means the same as
	`free(ptr)'.

I suggest you clarify the meaning of realloc(0,0).

The manual pages filter(1), mail(1), marshal(1), mlmgr(1), nedmail(1),
upasfs(4), pop3(8), send(8), and smtp(8) refer to aliasmail(1) which
does not exist.  The file /sys/man/8/INDEX.html refers to aliasmail(8)
which exists.  I suggest you decide if its aliasmail(8) or
aliasmail(1) and make the appropriate changes.

Upas/fs dies when working with an empty IMAP4 mail box.  There are two
problems, both in /sys/src/cmd/upas/fs/imap4.c:/^imap4read.  First,
when imap->nmsg is 0, the erealloc() call will fail.  Second, the
IMAP4 server I talk to (cyrus) does not like the command "UID FETCH
1:* UID" when there are no messages.  My fix was to change the
semantics of erealloc(_,0) and to avoid the offending IMAP command.
Diffs follow.

-dave

diff /n/dump/2002/0916/sys/src/cmd/upas/fs/imap4.c imap4.c
557,559c557,561
< 	imap4cmd(imap, "UID FETCH 1:* UID");
< 	if(!isokay(s = imap4resp(imap)))
< 		return s;
---
> 	if(imap->nmsg > 0){
> 		imap4cmd(imap, "UID FETCH 1:* UID");
> 		if(!isokay(s = imap4resp(imap)))
> 			return s;
> 	}
diff /n/dump/2002/0916/sys/src/cmd/upas/fs/mbox.c mbox.c
1358c1358,1362
< 	p = realloc(p, n);
---
> 	if(n==0){
> 		free(p);
> 		p = malloc(n);
> 	} else
> 		p = realloc(p, n);