From 3c0b3bdb4a1f132a6752ede8395a307b711da228 Mon Sep 17 00:00:00 2001
From: David du Colombier <0intro@gmail.com>
Date: Tue, 14 Jan 1992 00:00:00 +0000
Subject: [PATCH] Plan 9 from Bell Labs 1992-01-14

---
 gnot/devduart.c   |  2 +-
 pc/devfloppy.c    | 18 +++++++++---------
 pc/devhard.c      | 12 ++++++------
 pc/devlpt.c       |  2 +-
 pc/devuart.c      |  2 +-
 port/devarp.c     |  2 +-
 port/devcons.c    |  2 +-
 port/deviproute.c |  4 ++--
 port/devmnt.c     |  2 +-
 port/devmux.c     |  4 ++--
 port/devpipe.c    |  2 +-
 port/devproc.c    | 22 +++++++++++-----------
 port/devscc.c     |  6 +++---
 port/devsrv.c     |  2 +-
 port/devwren.c    |  8 ++++----
 port/error.h      | 42 +++++++++---------------------------------
 port/fault.c      | 10 +++++-----
 port/portfns.h    |  4 ++--
 port/proc.c       | 14 ++++++++------
 port/segment.c    | 20 ++++++++++----------
 port/stasync.c    |  2 +-
 port/stnoether.c  |  4 ++--
 port/stream.c     | 10 +++++-----
 port/sturp.c      |  2 +-
 port/swap.c       |  2 +-
 port/sysfile.c    | 10 +++++-----
 port/sysproc.c    | 14 +++++++-------
 power/devduart.c  | 10 +++++-----
 28 files changed, 106 insertions(+), 128 deletions(-)

diff --git a/gnot/devduart.c b/gnot/devduart.c
index c365bf1c202fad54b9d6a2edcb234ee775b7bdcc..bd20c5d194603b4279dd09243e0a6e41df0481ea 100644
--- a/gnot/devduart.c
+++ b/gnot/devduart.c
@@ -700,7 +700,7 @@ duartopen(Chan *c, int omode)
 	}
 
 	if(dp && dp->nostream)
-		errors("in use");
+		error(Einuse);
 
 	if((c->qid.path & CHDIR) == 0)
 		streamopen(c, &duartinfo);
diff --git a/pc/devfloppy.c b/pc/devfloppy.c
index 3117d6167cda1e77ed1f4eabd174999a77fe3695..c33b83d1133d596ff32c905c403c831f46299047 100644
--- a/pc/devfloppy.c
+++ b/pc/devfloppy.c
@@ -314,9 +314,9 @@ static void
 islegal(Chan *c, long n, Drive *dp)
 {
 	if(c->offset % dp->t->bytes)
-		errors("bad offset");
+		error(Ebadarg);
 	if(n % dp->t->bytes)
-		errors("bad len");
+		error(Ebadarg);
 }
 
 /*
@@ -341,7 +341,7 @@ changed(Chan *c, Drive *dp)
 	old = c->qid.vers;
 	c->qid.vers = dp->vers;
 	if(old && old!=dp->vers)
-		errors("disk changed");
+		error(Eio);
 }
 
 long
@@ -393,7 +393,7 @@ floppyread(Chan *c, void *a, long n)
 				if(i != nn){
 					if(i == 0)
 						break;
-					errors("floppy read err");
+					error(Eio);
 				}
 				dp->ccyl = cyl;
 				dp->chead = head;
@@ -796,7 +796,7 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 	 */
 	dp->len = n;
 	if(floppyseek(dp, off) < 0)
-		errors("seeking floppy");
+		error(Eio);
 
 /*print("tcyl %d, thead %d, tsec %d, addr %lux, n %d\n",
 	dp->tcyl, dp->thead, dp->tsec, a, dp->len);/**/
@@ -823,7 +823,7 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 	if(floppycmd() < 0){
 		spllo();
 		print("xfer cmd failed\n");
-		errors("floppy command failed");
+		error(Eio);
 	}
 
 	/*
@@ -838,14 +838,14 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 	if(fl.nstat < 7){
 		print("xfer result failed %lux\n", inb(Pmsr));
 		fl.confused = 1;
-		errors("floppy result failed");
+		error(Eio);
 	}
 	if((fl.stat[0] & Codemask)!=0 || fl.stat[1] || fl.stat[2]){
 		print("xfer failed %lux %lux %lux\n", fl.stat[0],
 			fl.stat[1], fl.stat[2]);
 		print("offset %lud len %d\n", off, dp->len);
 		dp->confused = 1;
-		errors("floppy drive lost");
+		error(Eio);
 	}
 
 	/*
@@ -856,7 +856,7 @@ floppyxfer(Drive *dp, int cmd, void *a, long off, long n)
 	offset = offset * c2b[fl.stat[6]];
 	if(offset != off+dp->len){
 		dp->confused = 1;
-		errors("floppy drive lost");
+		error(Eio);
 	}
 
 	dp->lasttouched = m->ticks;
diff --git a/pc/devhard.c b/pc/devhard.c
index 66d1666caf10fe2194c067e6aea077365def77ff..3d8b7f49acf44d14ab5d2de58a55f8cf681b665f 100644
--- a/pc/devhard.c
+++ b/pc/devhard.c
@@ -239,7 +239,7 @@ hardattach(char *spec)
 				break;
 			default:
 				print("unknown hard disk type\n");
-				errors("unknown hard disk type");
+				error(Egreg);
 			}
 			dp->bytes = 512;
 			dp->cap = dp->bytes * dp->cyl * dp->heads * dp->sectors;
@@ -349,7 +349,7 @@ hardwrite(Chan *c, void *a, long n)
 	Controller *cp;
 
 	if(c->qid.path == CHDIR)
-		errors("can't write directory");
+		error(Eisdir);
 
 	dp = &hard[DRIVE(c->qid.path)];
 	pp = &dp->p[PART(c->qid.path)];
@@ -432,7 +432,7 @@ cmdreadywait(Controller *cp)
 	while((inb(cp->pbase+Pstatus) & (Sready|Sbusy)) != Sready)
 		if(TK2MS(m->ticks - start) > 1){
 print("cmdreadywait failed\n");
-			errors("disk not responding");
+			error(Eio);
 		}
 }
 
@@ -450,7 +450,7 @@ hardxfer(Drive *dp, Partition *pp, int cmd, long start, long len)
 	int loop;
 
 	if(dp->online == 0)
-		errors("disk offline");
+		error(Eio);
 
 	/*
 	 *  cut transfer size down to disk buffer size
@@ -510,7 +510,7 @@ print("\tnsecs %d, sofar %d\n", cp->nsecs, cp->sofar);/**/
 print("hd%d err: status %lux, err %lux\n", dp-hard, cp->status, cp->error);
 print("\ttcyl %d, tsec %d, thead %d\n", cp->tcyl, cp->tsec, cp->thead);
 print("\tnsecs %d, sofar %d\n", cp->nsecs, cp->sofar);
-		errors("disk I/O error");
+		error(Eio);
 	}
 
 	return cp->nsecs*dp->bytes;
@@ -569,7 +569,7 @@ hardident(Drive *dp)
 	sleep(&cp->r, cmddone, cp);
 	if(cp->status & Serr){
 		print("bad disk ident status\n");
-		errors("disk I/O error");
+		error(Eio);
 	}
 	memmove(&dp->id, cp->buf, dp->bytes);
 
diff --git a/pc/devlpt.c b/pc/devlpt.c
index 6decbcee2253169a3ba3b7cdda08f60fed3243a0..6b75e0139b8aa72b15f82914efe326658efa5261 100644
--- a/pc/devlpt.c
+++ b/pc/devlpt.c
@@ -88,7 +88,7 @@ lptattach(char *spec)
 	int i  = (spec && *spec) ? strtol(spec, 0, 0) : 1;
 
 	if(i < 1 || i > NDEV)
-		errors("spec out of range");
+		error(Ebadarg);
 	c = devattach('L', spec);
 	c->dev = i-1;
 	return c;
diff --git a/pc/devuart.c b/pc/devuart.c
index 503aeb924b4ff217df5c70a574efc4715f227547..96fbc2ce8240530b18046712a4d13002e1fbbd60 100644
--- a/pc/devuart.c
+++ b/pc/devuart.c
@@ -655,7 +655,7 @@ uartopen(Chan *c, int omode)
 	}
 
 	if(up && up->nostream)
-		errors("in use");
+		error(Einuse);
 
 	if((c->qid.path & CHDIR) == 0)
 		streamopen(c, &uartinfo);
diff --git a/port/devarp.c b/port/devarp.c
index 243c70f13ab33b4361c1f1ec30e6e8d5254fae73..2acd1e9afcce9a5f780bd6073fe9b58f99c5a1e8 100644
--- a/port/devarp.c
+++ b/port/devarp.c
@@ -244,7 +244,7 @@ arpwrite(Chan *c, char *a, long n, ulong offset)
 				error(Ebadarg);
 
 			if(arpdelete(field[1]) < 0)
-				error(Ebadaddr);
+				error(Enetaddr);
 		}
 	case arpdataqid:
 		if(n != sizeof(Arpentry))
diff --git a/port/devcons.c b/port/devcons.c
index 416bf1737ca6e002bef85cc770b2912a04006938..57499479b9d3d28bd473ab34c77b34c1b42d8567 100644
--- a/port/devcons.c
+++ b/port/devcons.c
@@ -818,7 +818,7 @@ conswrite(Chan *c, void *va, long n, ulong offset)
 			error(Ebadarg);
 		decrypt(evekey, a, n);
 		if(memcmp(u->p->pgrp->crypt->chal, a, 8) != 0)
-			error(Eauth);
+			error(Eperm);
 		strncpy(u->p->user, a+8, NAMELEN);
 		u->p->user[NAMELEN-1] = '\0';
 		memmove(u->p->pgrp->crypt->key, a+NAMELEN+DESKEYLEN, DESKEYLEN);
diff --git a/port/deviproute.c b/port/deviproute.c
index e0ea9297f88875f03f8a4204293cfca9ebabe0f8..509c8a9e9825a21754a225e44e010777c6fef234 100644
--- a/port/deviproute.c
+++ b/port/deviproute.c
@@ -97,7 +97,7 @@ ipaddroute(ulong dst, ulong mask, ulong gate)
 	 *  filter out impossible requests
 	 */
 	if((dst&mask) != dst)
-		error(Ebadaddr);
+		error(Enetaddr);
 
 	/*
 	 *  see if we already have a route for
@@ -118,7 +118,7 @@ ipaddroute(ulong dst, ulong mask, ulong gate)
 	}
 	if(free == 0){
 		unlock(&iprtab);
-		error(Enoroute);
+		exhausted("routes");
 	}
 
 	/*
diff --git a/port/devmnt.c b/port/devmnt.c
index ffdb0c8b9028a312d2f04f6c44b8039f59bd31aa..05ba90538eb1b7de2c209120d84270bfa22a6eea 100644
--- a/port/devmnt.c
+++ b/port/devmnt.c
@@ -143,7 +143,7 @@ mntattach(char *muxattach)
 	lock(&mntalloc);
 	if(mntalloc.mntfree == 0) {
 		unlock(&mntalloc);
-		error(Enomntdev);
+		exhausted("mount devices");
 	}
 	m = mntalloc.mntfree;
 	mntalloc.mntfree = m->list;	
diff --git a/port/devmux.c b/port/devmux.c
index 8259bf4606195e102e8ac90f807754161fb1e631..01b3a2937f0a0f80363eb3437495163a418a0c1f 100644
--- a/port/devmux.c
+++ b/port/devmux.c
@@ -275,7 +275,7 @@ muxcreate(Chan *c, char *name, int omode, ulong perm)
 	}
 
 	if(m == e)
-		error(Enomux);
+		exhausted("multiplexers");
 
 	strncpy(m->name, name, NAMELEN);
 	strncpy(m->user, u->p->user, NAMELEN);
@@ -610,7 +610,7 @@ muxreadq(Mux *m, Dtq *q, char *va, ulong n)
 	while(!havedata(q)) {
 		sleep(&q->r, havedata, q);
 		if(m->headopen == 0)
-			errors(Emuxshutdown);
+			error(Emuxshutdown);
 	}
 
 	nread = 0;
diff --git a/port/devpipe.c b/port/devpipe.c
index 44797d88ab8414b29a44a69728521da989fcdcd7..dff38d9ca521e8683234ec5566b8176aaf243884 100644
--- a/port/devpipe.c
+++ b/port/devpipe.c
@@ -79,7 +79,7 @@ pipeattach(char *spec)
 	if(pipealloc.free == 0){
 		unlock(&pipealloc);
 		close(c);
-		error(Enopipe);
+		exhausted("pipes");
 	}
 	p = pipealloc.free;
 	pipealloc.free = p->next;
diff --git a/port/devproc.c b/port/devproc.c
index 0d183e39f8679f59b4632bf97591f40239d8fa15..1b73c44dee954c58ca503aa25059379556a5d28d 100644
--- a/port/devproc.c
+++ b/port/devproc.c
@@ -174,7 +174,7 @@ procopen(Chan *c, int omode)
 		c->pgrpid.vers = pg->pgrpid;
 		break;
 	default:
-		pprint("unknown qid in devopen\n");
+		pprint("procopen %lux\n", c->qid);
 		error(Egreg);
 	}
 
@@ -349,7 +349,7 @@ procread(Chan *c, void *va, long n, ulong offset)
 		if(offset+n > j)
 			n = j-offset;
 		if(n == 0 && offset == 0)
-			errors("no segments");
+			exhausted("segments");
 		memmove(a, &statbuf[offset], n);
 		return n;
 	}
@@ -392,7 +392,7 @@ procwrite(Chan *c, void *va, long n, ulong offset)
 	switch(QID(c->qid)){
 	case Qmem:
 		if(p->state != Stopped)
-			errors("not stopped");
+			error(Ebadctl);
 
 		if(offset >= USERADDR && offset <= USERADDR+BY2PG-1) {
 			pg = p->upage;
@@ -411,7 +411,7 @@ procwrite(Chan *c, void *va, long n, ulong offset)
 			ur = pxu->dbgreg;
 			if(offset < (ulong)ur || hi > (ulong)ur+sizeof(Ureg)) {
 				kunmap(k);
-				errors("bad u-area address");
+				error(Ebadarg);
 			}
 			ur = (Ureg*)(b+((ulong)ur-USERADDR));
 			setregisters(ur, b+(offset-USERADDR), a, n);
@@ -427,7 +427,7 @@ procwrite(Chan *c, void *va, long n, ulong offset)
 
 	case Qnote:
 		if(p->kp)
-			errors("can't note kproc");
+			error(Eperm);
 		k = kmap(p->upage);
 		up = (User*)VA(k);
 		if(up->p != p){
@@ -441,7 +441,7 @@ procwrite(Chan *c, void *va, long n, ulong offset)
 		memmove(buf, va, n);
 		buf[n] = 0;
 		if(!postnote(p, 0, buf, NUser))
-			error(Enonote);
+			exhausted("notes");
 		break;
 
 	default:
@@ -462,7 +462,7 @@ proctext(Chan *c, Proc *p)
 
 	s = p->seg[TSEG];
 	if(s == 0)
-		errors("no text segment");
+		error(Enonexist);
 	if(p->state==Dead)
 		error(Eprocdied);
 
@@ -524,7 +524,7 @@ procstopwait(Proc *p, int ctl)
 	int pid;
 
 	if(p->pdbg)
-		errors("debugged already");
+		error(Einuse);
 	if(procstopped(p))
 		return;
 
@@ -573,14 +573,14 @@ procctlreq(Proc *p, char *va, int n)
 		procstopwait(p, 0);
 	else if(strncmp(buf, "startstop", 9) == 0) {
 		if(p->state != Stopped)
-			errors("not stopped");
+			error(Ebadctl);
 		p->procctl = Proc_traceme;
 		ready(p);
 		procstopwait(p, Proc_traceme);
 	}
 	else if(strncmp(buf, "start", 5) == 0) {
 		if(p->state != Stopped)
-			errors("not stopped");
+			error(Ebadctl);
 		ready(p);
 	}
 	else
@@ -607,7 +607,7 @@ procctlmemio(Proc *p, ulong offset, int n, void *va, int read)
 	for(;;) {
 		s = seg(p, offset, 1);
 		if(s == 0)
-			errors("not in address space");
+			error(Ebadarg);
 
 		if(offset+n >= s->top)
 			n = s->top-offset;
diff --git a/port/devscc.c b/port/devscc.c
index 1dc3c83a746f7fd312613ee14d5824b0cef50040..70909c2d1e29d1201f185074ea4534033ec1b9a6 100644
--- a/port/devscc.c
+++ b/port/devscc.c
@@ -149,7 +149,7 @@ sccsetbaud(SCC *sp, int rate)
 	int brconst;
 
 	if(rate == 0)
-		errors("bad baud rate");
+		error(Ebadctl);
 
 	brconst = (sp->freq+16*rate-1)/(2*16*rate) - 2;
 
@@ -631,7 +631,7 @@ sccopen(Chan *c, int omode)
 	if(c->qid.path != CHDIR){
 		sp = scc[STREAMID(c->qid.path)];
 		if(sp->nostream)
-			errors("in use");
+			error(Einuse);
 		streamopen(c, &sccinfo);
 	}
 	return devopen(c, omode, sccdir, 2*nscc, devgen);
@@ -667,7 +667,7 @@ sccread(Chan *c, void *buf, long n, ulong offset)
 		sprint(b, "%d", STREAMID(c->qid.path));
 		return stringread(buf, n, b, offset);
 	}
-	errors("bad qid");
+	error(Egreg);
 }
 
 long
diff --git a/port/devsrv.c b/port/devsrv.c
index 9265351e850a0667c58c83d76666ab3352c392f6..0486b6fd2dcc73ad2a726a578bec6c8e472a263a 100644
--- a/port/devsrv.c
+++ b/port/devsrv.c
@@ -124,7 +124,7 @@ srvcreate(Chan *c, char *name, int omode, ulong perm)
 			error(Einuse);
 	}
 	if(j == -1)
-		error(Enosrv);
+		exhausted("server slots");
 	sp = &srv[j];
 	sp->chan = c;
 	unlock(&srvlk);
diff --git a/port/devwren.c b/port/devwren.c
index 15cd590074272b5061ced1db0ca15871f5f01f85..ed0921e7469bcf739cb12cda8be9dc9b185f326d 100644
--- a/port/devwren.c
+++ b/port/devwren.c
@@ -55,12 +55,12 @@ wrendev(char *p)
 	if(p == 0 || p[0] == '\0')
 		return 0;
 	if(p[0] < '0' || p[0] > '7')
-		errors("bad scsi drive specifier");
+		error(Ebadarg);
 	drive = p[0] - '0';
 	unit = 0;
 	if(p[1]){
 		if(p[1] != '.' || p[2] < '0' || p[2] > '7' || p[3] != '\0')
-			errors("bad scsi unit specifier");
+			error(Ebadarg);
 		unit = p[2] - '0';
 	}
 	return (drive << 3) | unit;
@@ -197,8 +197,8 @@ wrenio(Chan *c, int write, char *a, ulong len, ulong offset)
 	ulong block, n, max, x;
 
 	d = &wren[DRIVE(c->qid.path)];
-	if(d->npart == 0)
-		errors("drive repartitioned");
+	if(d->npart == 0)			/* drive repartitioned */
+		error(Eio);
 	p = &d->p[PART(c->qid.path)];
 
 	block = offset / d->bytes + p->start;
diff --git a/port/error.h b/port/error.h
index 46c5fb60d072a41cca099f1310153bc6133be62a..3ef4c7ca67eef2fc71e519ee4acd6b4de52d8838 100644
--- a/port/error.h
+++ b/port/error.h
@@ -4,7 +4,6 @@ extern char Eunmount[];		/* not mounted */
 extern char Eunion[];		/* not in union */
 extern char Emountrpc[];	/* mount rpc error */
 extern char Eshutdown[];	/* mounted device shut down */
-extern char Enomntdev[];	/* no free mount devices */
 extern char Enocreate[];	/* mounted directory forbids creation */
 extern char Enonexist[];	/* file does not exist */
 extern char Ebadsharp[];	/* unknown device in # filename */
@@ -25,13 +24,11 @@ extern char Enobitmap[];	/* out of bitmap descriptors */
 extern char Enobitstore[];	/* out of bitmap storage */
 extern char Ebadfont[];		/* unallocated font */
 extern char Enofont[];		/* no free font descriptors */
-extern char Eauth[];		/* authentication failure */
-extern char Ebadaddr[];		/* bad network address */
+extern char Enetaddr[];		/* bad network address */
 extern char Emsgsize[];		/* message is too big for protocol */
 extern char Enetbusy[];		/* network device is busy or allocated */
 extern char Enoproto[];		/* network protocol not supported */
 extern char Enoport[];		/* network port not available */
-extern char Enoroute[];		/* no free routes */
 extern char Enoifc[];		/* bad interface or no free interface slots */
 extern char Enolisten[];	/* not announced */
 extern char Ehungup[];		/* write to hungup stream */
@@ -40,38 +37,17 @@ extern char Enodev[];		/* no free devices */
 extern char Enoenv[];		/* no free environment resources */
 extern char Emuxshutdown[];	/* mux server shut down */
 extern char Emuxbusy[];		/* all mux channels busy */
-extern char Enomux[];		/* no free multiplexers */
 extern char Emuxmsg[];		/* bad mux message format or mismatch */
-extern char Enopipe[];		/* no free pipes */
-
-extern char Enofd[];		/* no free file descriptors */
-extern char Ebadfd[];		/* fd out of range or not open */
-extern char Ebadexec[];		/* a.out header invalid */
-extern char Eioload[];		/* i/o error in demand load */
-extern char Enochild[];		/* no living children */
-extern char Enoseg[];		/* no free segments */
-extern char Ebadmount[];	/* inconsistent mount */
-extern char Ebaddirread[];	/* directory read not quantized */
-extern char Esegaddr[];		/* illegal segment addresses or size */
 extern char Eprocdied[];	/* process exited */
-extern char Enosrv[];		/* no free server slots */
-extern char Enoqueue[];		/* no free stream queues */
-extern char Ebadld[];		/* illegal line discipline */
-extern char Enostream[];	/* no free stream heads */
-extern char Ebadnet[];		/* illegal network address */
-extern char Enonote[];		/* note overflow */
-extern char Eintr[];		/* interrupted */
-extern char Edestbusy[];	/* datakit destination busy */
-extern char Edestotl[];		/* datakit destination out to lunch */
-extern char Enetotl[];		/* datakit controller out to lunch */
-extern char Erejected[];	/* datakit destination rejected call */
-extern char Ebadcnt[];		/* read count greater than requested */
+extern char Enochild[];		/* no living children */
+extern char Eioload[];		/* i/o error in demand load */
 extern char Enovmem[];		/* virtual memory allocation failed */
-extern char Enoasync[];		/* out of async stream modules */
-extern char Enetunreach[];	/* network unreachable */
+extern char Ebadld[];		/* illegal line discipline */
+extern char Ebadfd[];		/* fd out of range or not open */
+extern char Eisstream[];	/* seek on a stream */
+extern char Ebadexec[];		/* a.out header invalid */
 extern char Etimedout[];	/* connection timed out */
 extern char Econrefused[];	/* connection refused */
-extern char Eprotonosup[];	/* operation not supported by network protocol */
-extern char Eisstream[];	/* seek on a stream */
-extern char Enofilsys[];	/* out of filsys resources */
+extern char Enetunreach[];	/* network unreachable */
+extern char Eintr[];		/* interrupted */
 extern char Egreg[];		/* it's a thermal problem */
diff --git a/port/fault.c b/port/fault.c
index bf68eef4e51b73af7ecd9cad0252e39f4ad416f2..2f2ecd3932341d578e1613fc75849cc9fe09e5b5 100644
--- a/port/fault.c
+++ b/port/fault.c
@@ -8,7 +8,7 @@
 
 #define DPRINT
 
-void	faultexit(char*);
+void	faulterror(char*);
 
 int
 fault(ulong addr, int read)
@@ -190,7 +190,7 @@ pio(Segment *s, ulong addr, ulong soff, Page **p)
 			qunlock(&c->rdl);
 			kunmap(k);
 			putpage(new);
-			faultexit("sys: demand load I/O error");
+			faulterror("sys: demand load I/O error");
 		}
 
 		ask = s->flen-soff;
@@ -224,7 +224,7 @@ pio(Segment *s, ulong addr, ulong soff, Page **p)
 			putpage(new);
 			qlock(&s->lk);
 			qunlock(&s->lk);
-			faultexit("sys: page in I/O error");
+			faulterror("sys: page in I/O error");
 		}
 
 		n = (*devtab[c->type].read)(c, kaddr, BY2PG, daddr);
@@ -248,11 +248,11 @@ pio(Segment *s, ulong addr, ulong soff, Page **p)
 }
 
 void
-faultexit(char *s)
+faulterror(char *s)
 {
 	if(u->nerrlab) {
 		postnote(u->p, 1, s, NDebug);
-		errors(s);
+		error(s);
 	}
 	pexit(s, 0);
 }
diff --git a/port/portfns.h b/port/portfns.h
index e7d6cb8f8f252ca00fbb76d56c389880ce014d5e..c6f0ad35e8fe2803e2f82608f99302d7d236dcff 100644
--- a/port/portfns.h
+++ b/port/portfns.h
@@ -59,9 +59,9 @@ void	envpgclose(Env*);
 void	envpgcopy(Env*, Env*);
 int	eqchan(Chan*, Chan*, long);
 int	eqqid(Qid, Qid);
-void	error(char []);
-void	errors(char*);
+void	error(char*);
 long	execregs(ulong, ulong, ulong);
+void	exhausted(char*);
 void	exit(void);
 Block*	expandb(Block *, int);
 int	fault(ulong, int);
diff --git a/port/proc.c b/port/proc.c
index 59bbe5e1e8cf5d7424c69149be0d772b57de17f0..d3742989096342fa9641ef0f6df090256ad52d98 100644
--- a/port/proc.c
+++ b/port/proc.c
@@ -390,7 +390,7 @@ postnote(Proc *p, int dolock, char *n, int flag)
 	if(p->upage == 0){
 		if(dolock)
 			qunlock(&p->debug);
-		errors("noted process disappeared");
+		error(Eprocdied);
 	}
 
 	SET(k);
@@ -771,16 +771,18 @@ error(char err[])
 }
 
 void
-errors(char *err)
+nexterror(void)
 {
-	strncpy(u->error, err, ERRLEN);
-	nexterror();
+	gotolabel(&u->errlab[--u->nerrlab]);
 }
 
 void
-nexterror(void)
+exhausted(char *resource)
 {
-	gotolabel(&u->errlab[--u->nerrlab]);
+	char buf[ERRLEN];
+
+	sprint(buf, "no free %s", resource);
+	error(buf);
 }
 
 Waitq *
diff --git a/port/segment.c b/port/segment.c
index d35351d4100c187ea096a3f36e2f9d161b03f7e9..4ec6854db68d33c7e9c009e51a8137cfcc6d9321 100644
--- a/port/segment.c
+++ b/port/segment.c
@@ -57,7 +57,7 @@ newseg(int type, ulong base, ulong size)
 	Segment *s;
 
 	if(size > (SEGMAPSIZE*PTEPERTAB))
-		errors("segment too large");
+		error(Enovmem);
 
 	for(;;) {
 		lock(&segalloc);
@@ -335,7 +335,7 @@ ibrk(ulong addr, int seg)
 
 	s = u->p->seg[seg];
 	if(s == 0)
-		errors("no segment");
+		error(Ebadarg);
 
 	if(addr == 0)
 		return s->base;
@@ -346,7 +346,7 @@ ibrk(ulong addr, int seg)
 		/* We may start with the bss overlapping the data */
 		if(seg != BSEG || u->p->seg[DSEG] == 0 || addr < u->p->seg[DSEG]->base) {
 			qunlock(&s->lk);
-			errors("addr below segment");
+			error(Enovmem);
 		}
 		addr = s->base;
 	}
@@ -371,7 +371,7 @@ ibrk(ulong addr, int seg)
 		if(newtop >= ns->base && newtop < ns->top) {
 			qunlock(&s->lk);
 			pprint("segments overlap\n");
-			error(Esegaddr);
+			error(Enovmem);
 		}
 	}
 
@@ -424,7 +424,7 @@ segattach(Proc *p, ulong attr, char *name, ulong va, ulong len)
 
 	USED(p);
 	if(va&KZERO)					/* BUG: Only ok for now */
-		errors("bad virtual address");
+		error(Ebadarg);
 
 	validaddr((ulong)name, 1, 0);
 	vmemchr(name, 0, ~0);
@@ -434,7 +434,7 @@ segattach(Proc *p, ulong attr, char *name, ulong va, ulong len)
 			break;
 
 	if(sno == NSEG)
-		errors("no per process segments");
+		error(Enovmem);
 
 	va = va&~(BY2PG-1);
 	len = PGROUND(len);
@@ -445,17 +445,17 @@ segattach(Proc *p, ulong attr, char *name, ulong va, ulong len)
 			continue;	
 		if((newtop > ns->base && newtop <= ns->top) ||
 		   (va >= ns->base && va < ns->top))
-			errors("segments overlap");
+			error(Enovmem);
 	}
 
 	for(ps = physseg; ps->name; ps++)
 		if(strcmp(name, ps->name) == 0)
 			goto found;
 
-	errors("bad segment name");
+	error(Ebadarg);
 found:
 	if(len > ps->size)
-		errors("segment too long");
+		error(Enovmem);
 
 	attr &= ~SG_TYPE;			/* Turn off what we are not allowed */
 	attr |= ps->attr;			/* Copy in defaults */
@@ -480,7 +480,7 @@ syssegflush(ulong *arg)
 
 	s = seg(u->p, arg[0], 1);
 	if(s == 0)
-		errors("bad segment address");
+		error(Ebadarg);
 
 	s->flushme = 1;
 
diff --git a/port/stasync.c b/port/stasync.c
index c72533568277c6362d985e5d85da9c7a345b1973..818e03ff7ca59eafc467626bcd6786764933b411 100644
--- a/port/stasync.c
+++ b/port/stasync.c
@@ -113,7 +113,7 @@ asyncopen(Queue *q, Stream *s)
 		qunlock(ap);
 	}
 	if(ap == &async[conf.nasync])
-		error(Enoasync);
+		exhausted("async stream modules");
 	q->ptr = q->other->ptr = ap;
 
 	ap->inuse = 1;
diff --git a/port/stnoether.c b/port/stnoether.c
index 239b8b2b6e67cbbf56b1e3cdedd66794bde94489..8d5e5db19c240190ef45f359d7bc10b586c4b3a7 100644
--- a/port/stnoether.c
+++ b/port/stnoether.c
@@ -265,7 +265,7 @@ etherparse(uchar *to, char *from)
 	if(strchr(from, '.')) {
 		ip = ipparse(from);
 		if(ip == 0)
-			error(Ebadnet);
+			error(Enetaddr);
 
 		hnputl(nip, ip);			
 		if(arp_lookup(nip, to))
@@ -274,7 +274,7 @@ etherparse(uchar *to, char *from)
 #endif
 
 	if(strlen(from) != 12)
-		error(Ebadnet);
+		error(Enetaddr);
 
 	for(i = 0; i < 6; i++){
 		fdig = (*from++)&0x7f;
diff --git a/port/stream.c b/port/stream.c
index 2c7be3c378616610235f015aefd4c547d0c5b4b9..58645683accaecbd566a3530ae9444a933eae8d8 100644
--- a/port/stream.c
+++ b/port/stream.c
@@ -296,7 +296,7 @@ allocq(Qinfo *qi)
 
 	if(q == &qlist[conf.nqueue]){
 		print("no more queues\n");
-		error(Enoqueue);
+		exhausted("queues");
 	}
 
 	q->flag = QINUSE;
@@ -820,7 +820,7 @@ streamnew(ushort type, ushort dev, ushort id, Qinfo *qi, int noopen)
 	}
 	if(s == &slist[conf.nstream]){
 		print("no more streams\n");
-		error(Enostream);
+		exhausted("streams");
 	}
 	if(waserror()){
 		qunlock(s);
@@ -1159,7 +1159,7 @@ streamread(Chan *c, void *vbuf, long n)
 		if(bp == 0){
 			if(q->flag & QHUNGUP){
 				if(s->err)
-					errors((char*)s->err->rptr);
+					error((char*)s->err->rptr);
 				else if(s->hread++<3)
 					break;
 				else
@@ -1217,7 +1217,7 @@ qlook(Stream *s, char *name)
 		if(q == s->devq->other)
 			break;
 	}
-	errors("not found");
+	error(Ebadarg);
 }
 
 /*
@@ -1322,7 +1322,7 @@ streamwrite(Chan *c, void *a, long n, int docopy)
 	q = s->procq;
 	if(q->other->flag & QHUNGUP){
 		if(s->err)
-			errors((char*)(s->err->rptr));
+			error((char*)(s->err->rptr));
 		else
 			error(Ehungup);
 	}
diff --git a/port/sturp.c b/port/sturp.c
index db90733d32bdb7721b9255c59c9d73b6ab3f7961..97a95f28d4cb5082b77104726df9e87f43e62143 100644
--- a/port/sturp.c
+++ b/port/sturp.c
@@ -167,7 +167,7 @@ urpopen(Queue *q, Stream *s)
 	if(up == &urp[conf.nurp]){
 		q->ptr = 0;
 		WR(q)->ptr = 0;
-		errors("out of urp structures");
+		exhausted("urp structures");
 	}
 
 	q->ptr = q->other->ptr = up;
diff --git a/port/swap.c b/port/swap.c
index d174d1b63a13ae231ddcd9b56817922d04d29a0f..5e93539b3c25d813ccb4d2410163e662e6d8f7d2 100644
--- a/port/swap.c
+++ b/port/swap.c
@@ -330,7 +330,7 @@ setswapchan(Chan *c)
 {
 	if(swapimage.c) {
 		if(swapalloc.free != conf.nswap)
-			errors("swap channel busy");
+			error(Einuse);
 		close(swapimage.c);
 	}
 	incref(c);
diff --git a/port/sysfile.c b/port/sysfile.c
index 7b9d58ed73f5cf7ed14cd9ef31936a3badfd28d5..371fc3bd1576ba0d738fabba65a58c438bc5c285 100644
--- a/port/sysfile.c
+++ b/port/sysfile.c
@@ -26,7 +26,7 @@ newfd(Chan *c)
 			return i;
 		}
 	unlock(f);
-	error(Enofd);
+	exhausted("file descriptors");
 }
 
 Chan*
@@ -38,7 +38,7 @@ fdtochan(int fd, int mode, int chkmnt)
 	if(fd<0 || NFD<=fd || (c = u->p->fgrp->fd[fd])==0)
 		error(Ebadfd);
 	if(chkmnt && (c->flag&CMSG))
-		errors("channel is mounted");
+		error(Ebadusefd);
 	if(mode<0 || c->mode==ORDWR)
 		return c;
 	if((mode&OTRUNC) && c->mode==OREAD)
@@ -262,7 +262,7 @@ sysread(ulong *arg)
 	if(c->qid.path & CHDIR){
 		n -= n%DIRLEN;
 		if(c->offset%DIRLEN || n==0)
-			error(Ebaddirread);
+			error(Etoosmall);
 	}
 	if((c->qid.path&CHDIR) && c->mnt)
 		n = unionread(c, (void*)arg[1], n);
@@ -426,9 +426,9 @@ bindmount(ulong *arg, int ismount)
 		nexterror();
 	}
 	if((c0->qid.path^c1->qid.path) & CHDIR)
-		error(Ebadmount);
+		error(Emount);
 	if(flag && !(c0->qid.path&CHDIR))
-		error(Ebadmount);
+		error(Emount);
 	ret = mount(c0, c1, flag);
 	poperror();
 	close(c1);
diff --git a/port/sysproc.c b/port/sysproc.c
index e08391abe709761731f14153c5f2ecedc2f0c5d1..0fc24ed95a2e81bee3c3c6b1dc12da36bd6bfa40 100644
--- a/port/sysproc.c
+++ b/port/sysproc.c
@@ -259,7 +259,7 @@ sysexec(ulong *arg)
 	 * Build the stack segment, putting it in kernel virtual for the moment
 	 */
 	if(spage > TSTKSIZ)
-		errors("too many arguments");
+		error(Enovmem);
 
 	 
 	p->seg[ESEG] = newseg(SG_STACK, TSTKTOP-USTKSIZE, USTKSIZE/BY2PG);
@@ -528,14 +528,14 @@ syssegbrk(ulong *arg)
 				switch(s->type&SG_TYPE) {
 				case SG_TEXT:
 				case SG_DATA:
-					errors("bad segment type");
+					error(Ebadarg);
 				default:
 					return ibrk(arg[1], i);
 				}
 			}
 		}
 
-	errors("not in address space");
+	error(Ebadarg);
 }
 
 long
@@ -560,12 +560,12 @@ syssegdetach(ulong *arg)
 			qunlock(&s->lk);
 		}
 
-	errors("not in address space");
+	error(Ebadarg);
 
 found:
 	if((ulong)arg >= s->base && (ulong)arg < s->top) {
 		qunlock(&s->lk);
-		errors("illegal address");
+		error(Ebadarg);
 	}
 	u->p->seg[i] = 0;
 	qunlock(&s->lk);
@@ -585,13 +585,13 @@ syssegfree(ulong *arg)
 	from = PGROUND(arg[0]);
 	s = seg(u->p, from, 1);
 	if(s == 0)
-		errors("not in address space");
+		error(Ebadarg);
 
 	pages = (arg[1]+BY2PG-1)/BY2PG;
 
 	if(from+pages*BY2PG > s->top) {
 		qunlock(&s->lk);
-		errors("segment too short");
+		error(Ebadarg);
 	}
 
 	mfreeseg(s, from, pages);
diff --git a/power/devduart.c b/power/devduart.c
index 58821498e42b0ce796b4aa0b09021816fcb29c41..57d76f628bdf20f3ef0b450cd5d30f4439b4222b 100644
--- a/power/devduart.c
+++ b/power/devduart.c
@@ -232,7 +232,7 @@ duartbaud(Duartport *dp, int b)
 		x = BD300;
 		break;
 	default:
-		errors("bad baud rate");
+		error(Ebadarg);
 	}
 	if(x & 0x0100)
 		dp->duart->ipc_acr = duartacr |= 0x80;
@@ -770,7 +770,7 @@ duartopen(Chan *c, int omode)
 	}
 
 	if(dp && dp->nostream)
-		errors("in use");
+		error(Einuse);
 
 	if((c->qid.path & CHDIR) == 0)
 		streamopen(c, &duartinfo);
@@ -814,7 +814,7 @@ duartread(Chan *c, void *buf, long n, ulong offset)
 		return 1;
 	}
 
-	errors("no such duart type");
+	error(Egreg);
 }
 
 long
@@ -827,14 +827,14 @@ void
 duartremove(Chan *c)
 {
 	USED(c);
-	errors("can't remove a duart");
+	error(Eperm);
 }
 
 void
 duartwstat(Chan *c, char *dp)
 {
 	USED(c);
-	errors("can't write a duart");
+	error(Eperm);
 }
 
 int