sources-request@panda.UUCP (01/23/86)
Mod.sources: Volume 3, Issue 92
Submitted by: princeton!down!honey (Peter Honeyman)
#! /bin/sh
# This is a shell archive, meaning:
# 1. Remove everything above the #! /bin/sh line.
# 2. Save the resulting text in a file.
# 3. Execute the file with /bin/sh (not csh) to create the files:
# README
# CHANGES
# Makefile
# config.h
# def.h
# make.v8
# pathalias.1
# This archive created: Wed Jan 22 19:21:55 1986
export PATH; PATH=/bin:$PATH
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if test -f 'README'
then
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else
sed 's/^X//' << \SHAR_EOF > 'README'
XFrom princeton!honey Sun Jan 19 18:35:58 EST 1986
To: whom it may concern
Subject: pathalias instructions
edit config.h
make
if getopt is undefined, obtain a copy from mod.sources. pathalias input
is regularly published in mod.map.
peter
ps:
pathalias, written by steve bellovin and peter honeyman, is in the public
domain, and may be used by any person or organization, in any way and for
any purpose.
pps:
There is no warranty of merchantability nor any warranty of fitness for
a particular purpose nor any other warranty, either express or implied,
as to the accuracy of the enclosed materials or as to their suitability
for any particular purpose. Accordingly, the authors assume no respon-
sibility for their use by the recipient. Further, the authors assume
no obligation to furnish any assistance of any kind whatsoever, or to
furnish any additional information or documentation.
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-- mod.sources, 4.3bsd, 1/86
Improved alias treatment.
Routes to domain gateways.
New domain treatment -- leading dot in name implies domain.
Print fully qualified domain name for private hosts.
Link/host tracing (-t option).
Use getopt().
-- mod.sources, 8/85
Private hosts documented.
Homegrown scanner -- it's true what they say about lex.
Makedb.
Domains and gateways.
DEAD back link.
-- net.sources, 1/85
No ! in dbm key.
Network character must be one of !@%: -- dot is dead.
Private hosts.
Discourage hybrid addresses.
Magic @ <-> % rule.
-- 1983-1984
Reverse sense of the -c (cost) flag.
Use cheapest among duplicate links.
Elide network names in output.
-- epoch (smb version)
SHAR_EOF
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then
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fi
fi
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if test -f 'Makefile'
then
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else
cat << \SHAR_EOF > 'Makefile'
#!/bin/make -f
# pathalias -- by steve bellovin, as told to peter honeyman
# if you can't or don't intend to use dbm files, don't bother with makedb
DBM = -ldbm
# or if you roll your own ...
# DBM = dbm.o
CC = cc
CFLAGS = -O
LDFLAGS = -s
YFLAGS = -d
OBJ = addlink.o addnode.o extern.o local.o main.o mapit.o mapaux.o mem.o parse.o printit.o
HDRS = def.h config.h
CSRC = addlink.c addnode.c extern.c local.c main.c mapit.c mapaux.c mem.c printit.c
SRC = $(CSRC) parse.y
LSRC = $(CSRC) parse.c
pathalias: $(OBJ)
$(CC) $(LDFLAGS) $(OBJ) -o pathalias
all: pathalias makedb
$(OBJ): $(HDRS)
parse.c: parse.y $(HDRS)
$(YACC) $(YFLAGS) parse.y
mv y.tab.c parse.c
makedb: makedb.o
$(CC) $(LDFLAGS) makedb.o $(DBM) -o makedb
makedb.o: config.h
clean:
rm -f *.o y.tab.? parse.c
clobber: clean
rm -f pathalias makedb
tags: $(SRC) $(HDRS) makedb.c
ctags -w $(HDRS) $(SRC)
bundle:
@bundle README CHANGES pathalias.1 Makefile ${HDRS} ${SRC} makedb.c
lint: $(LSRC)
lint $(CFLAGS) $(LSRC)
lint makedb.c
install:
@echo "install pathalias according to local conventions"
SHAR_EOF
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then
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fi
fi
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/* pathalias -- by steve bellovin, as told to peter honeyman */
#define STRCHR /* have strchr, not index -- probably system v */
#define UNAME /* have uname() -- probably system v or 8th ed. */
#define MEMSET /* have memset() -- probably system v or 8th ed. */
/* #define GETHOSTNAME /* have gethostname() -- probably 4.2bsd */
/* #define BZERO /* have bzero() -- probably 4.2bsd */
/* default place for dbm output of makedb (or use -o file at run-time) */
#define ALIASDB "/usr/local/lib/palias"
/**************************************************************************
* *
* +--------------------------------------------------------------------+ *
* | | *
* | END OF CONFIGURATION SECTION | *
* | | *
* | EDIT NO MORE | *
* | | *
* +--------------------------------------------------------------------+ *
* *
**************************************************************************/
#ifdef MAIN
#ifndef lint
static char *c_sccsid = "@(#)config.h 8.1 (down!honey) 86/01/19";
#endif /*lint*/
#endif /*MAIN*/
/*
* malloc/free fine tuned for pathalias.
*
* MYMALLOC should work everwhere, so it's not a configuration
* option (anymore). nonetheless, if you're getting strange
* core dumps (or panics!), comment out the following manifest,
* and use the inferior C library malloc/free.
*
* report problems to princeton!honey.
*/
#define MYMALLOC /**/
#ifdef MYMALLOC
#define malloc mymalloc
#define calloc(n, s) malloc ((n)*(s))
#define free(s)
#define cfree(s)
extern char *memget();
#endif
#ifdef STRCHR
#define index strchr
#define rindex strrchr
#else
#define strchr index
#define strrchr rindex
#endif
#ifdef BZERO
#define strclear(s, n) ((void) bzero((s), (n)))
#else /*!BZERO*/
#ifdef MEMSET
extern char *memset();
#define strclear(s, n) ((void) memset((s), 0, (n)))
#else /*!MEMSET*/
extern void strclear();
#endif /*MEMSET*/
#endif /*BZERO*/
extern char *malloc();
extern char *strcpy(), *index(), *rindex();
SHAR_EOF
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then
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fi
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then
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else
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/* pathalias -- by steve bellovin, as told to peter honeyman */
#ifndef lint
#ifdef MAIN
static char *h_sccsid = "@(#)def.h 8.1 (down!honey) 86/01/19";
#endif /*MAIN*/
#endif /*lint*/
#include <stdio.h>
#include <ctype.h>
#include "config.h"
typedef long Cost;
typedef struct node node;
typedef struct link link;
#ifdef lint
#define vprintf fprintf
#else /*!lint -- this gives null effect warning*/
/* because it's there ... */
#define vprintf !Vflag ? 0 : fprintf
#endif /*lint*/
#define NTRACE 16 /* can trace up to NTRACE hosts/links */
/* scanner states (yylex, parse) */
#define OTHER 0
#define COSTING 1
#define NEWLINE 2
#define isnetc(c) ((c)=='!' || (c)==':' || (c)=='@' || (c)=='%')
#define dirbits(c) (c)
/* flags for n_flag */
#define ISPRIVATE 0x0001 /* this node invisible outside its definition file */
#define COLLISION 0x0002 /* collides with a private host name */
#define ATSIGN 0x0004 /* seen an at sign? used for magic @/% rules */
#define MAPPED 0x0008 /* done mapping this node */
#define NDEAD 0x0010 /* node is dead */
#define HASLEFT 0x0020 /* route has a left side net character */
#define HASRIGHT 0x0040 /* route has a right side net character */
#define NNET 0x0080 /* node is a network name */
#define INDFS 0x0100 /* used when removing net cycles */
#define DUMP 0x0200 /* we have dumped this net's edges */
#define GATEWAYIN 0x0400 /* heaped via gatewayed net */
#define ISADOMAIN(n) ((n)->n_name[0] == '.')
#define ISANET(n) (((n)->n_flag & NNET) || ISADOMAIN(n))
#define DEADHOST(n) (((n)->n_flag & (NNET | NDEAD)) == NDEAD)
#define GATEWAYED(n) (((n)->n_flag & (NNET | NDEAD)) == (NNET | NDEAD) || ISADOMAIN(n))
/*
* save some space in nodes -- there are > 10,000 allocated!
*
* node *n_net others in this network (parsing)
* node *n_root root of net cycle (mapping)
*
* node *n_private other privates in this file (parsing)
* char *n_parent parent in shortest path tree (mapping)
*
*/
#define n_root n_net_root
#define n_net n_net_root
#define n_private n_private_parent
#define n_parent n_private_parent
/* WARNING: if > 2^16 nodes, type of n_tloc must change */
struct node {
char *n_name; /* host name */
link *n_link; /* head of adjacency list */
node *n_net_root;
node *n_private_parent;
Cost n_cost; /* cost to this host */
unsigned short n_tloc; /* back ptr to heap/hash table */
short n_flag; /* see manifests above */
};
#define DEFNET '!' /* default network operator */
#define DEFDIR LLEFT /* host on left is default */
#define DEFCOST ((Cost) 4000) /* default cost of a link */
#define INF ((Cost) 30000000) /* infinitely expensive link */
/* data structure for adjacency list representation */
/* flags for l_dir */
/*
* there's an ugly dependency between the following manifests and the
* variable Netchars = "!:^@%", defined in extern.c. this saves 2
* bytes per link (of which there are well over 20k). this does not
* mean i'm satsified with bad design.
*/
#define NETDIR(l) ((l)->l_flag & LDIR)
#define NETCHAR(l) (Netchars[(l)->l_flag & LNETCHARS])
#define LNETCHARS 0x3
#define LBANG 0x0
#define LCOLON 0x1
#define LAT 0x2
#define LPERCENT 0x3
#define LDIR 0x8 /* 0 for left, 1 for right */
#define LRIGHT 0x0 /* user@host style */
#define LLEFT 0x8 /* host!user style */
#define LDEAD 0x10 /* this link is dead */
#define LTREE 0x20 /* member of shortest path tree */
#define LALIAS 0x40 /* alias */
#define LGATEWAY 0x80 /* this link is a gateway */
/*
* borrow a field for link/node tracing
*
* link *l_next; rest of adjacency list (not tracing)
* link *l_from; source node (tracing) -- requires a cast
*
*/
#define l_next l_next_from
#define l_from l_next_from
struct link {
link *l_next_from;
node *l_to; /* adjacent node */
Cost l_cost; /* edge cost */
char l_flag; /* right/left syntax */
};
/*
* static functions don't show up in prof(1), so ...
* someday i'll be done profiling.
* yeah, sure, like when hell freezes over.
*/
#define STATIC /*static*/
/* external functions */
extern node *addnode(), *newnode(), **newtable(), *addprivate();
extern link *addlink(), *addgateway(), *newlink();
extern char *strsave(), *local();
extern void pack();
/* external variables */
extern char *optarg;
extern int optind;
extern node *Home;
extern char *Cfile;
extern char **Ifiles;
extern char *ProgName;
extern int Lineno;
extern node **Table;
extern long Tabsize;
extern char *Netchars;
extern int Vflag;
extern int Cflag;
extern int Iflag;
extern int Tflag;
extern int Ncount;
extern int Lcount;
extern char *Graphout;
extern char *Linkout;
extern node *Private;
extern long Hashpart;
extern int Scanstate;
SHAR_EOF
if test 4683 -ne "`wc -c < 'def.h'`"
then
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fi
fi
echo shar: extracting "'make.v8'" '(3555 characters)'
if test -f 'make.v8'
then
echo shar: will not over-write existing file "'make.v8'"
else
cat << \SHAR_EOF > 'make.v8'
#!/bin/make -f
# pathalias -- by steve bellovin, as told to peter honeyman
# if you can't or don't intend to use dbm files, don't bother with makedb
DBM = -ldbm
# or if you roll your own ...
# DBM = dbm.o
CC = cc -g -p
CFLAGS =
LDFLAGS =
YFLAGS = -d
OBJ = addlink.o addnode.o extern.o local.o main.o mapit.o mapaux.o mem.o parse.o printit.o
HDRS = def.h config.h
CSRC = addlink.c addnode.c extern.c local.c main.c mapit.c mapaux.c mem.c printit.c
SRC = $(CSRC) parse.y
LSRC = $(CSRC) parse.c
pathalias: & $(OBJ)
$(CC) $(LDFLAGS) $(OBJ) -o pathalias
all: pathalias makedb
$(OBJ): def.h
# if touch had a proper exit status, this would work...
def.h: config.h
-touch -c def.h
get -s sccs/s.def.h
parse.c: parse.y def.h
$(YACC) $(YFLAGS) parse.y
mv y.tab.c parse.c
makedb: makedb.o
$(CC) makedb.o $(DBM) -o makedb
makedb.o: config.h
clean:
rm -f *.o y.tab.? parse.c
tags: $(SRC) $(HDRS) makedb.c
ctags -w $^
bundle: README CHANGES pathalias.1 Makefile ${HDRS} ${SRC} makedb.c make.v8
@bundle $^
bundle1: README CHANGES pathalias.1 Makefile def.h config.h addlink.c
@bundle $^
bundle2: addnode.c extern.c local.c main.c mapit.c
@bundle $^
bundle3: mapaux.c mem.c printit.c parse.y makedb.c make.v8
@bundle $^
make.v8: makefile
@cp makefile make.v8
lint: $(LSRC)
lint $(CFLAGS) $(LSRC)
lint makedb.c
# v8 make rules for sccs
%: & sccs/s.%
get -s sccs/s.$%
# the remainder is site specific and can be deleted. it doesn't have
# to be this complicated, but a makefile tends to swell after three or
# four years.
# hosts running delivermail
DELIVERMAIL = tilt
# hosts running sendmail
SENDMAIL = quirky flakey yoyo panic
# all neighbors
NEIGHBORS = princeton ${DELIVERMAIL} ${SENDMAIL}
# including me
SITES = down ${NEIGHBORS}
PATHFILES = paths/[^.]* paths.bell/[^.]* paths.internet/[^.]* path.map/[^.]*
# from observation and rumor. avoid like the plague
DEADHOSTS = -d tucc -d netword -d harvard -d whuxlb -d conejo
DEADLINKS = -d siemens!uiucdcs -d allegra!rcalabs -d amdcad!chi -d allegra!shasta -d allegra!olympus -d shasta!imagen
DEADNETS = -d internet
DEAD = ${DEADHOSTS} ${DEADLINKS} ${DEADNETS}
# map output (input, really) to lower case. dead links.
ARGS = -i
paths: ${SITES}
down: paths/princeton
time -v pathalias -v ${ARGS} $(DEAD) $(PATHFILES) 2>ERRORS > down.new
sort -o down down.new
# DELIVERMAIL and SENDMAIL have exactly the same links as down, so turn
# down %s
# up up!%s
# into
# up %s
# down down!%s
${DELIVERMAIL}: down
sed -e 's/^down %s$$/$@ %s/' \
-e 's/^$@ $@!%s$$/down down!%s/'\
-e 's/^/0 /' down | sort > $@
# reorder the output and generate phoney costs for sendmail neighbors
${SENDMAIL}: down
sed -e 's/^down %s$$/$@ %s/' \
-e 's/$@ $@!%s$$/down down!%s/'\
-e 's/ / 0 /' down |sort > $@
# install everywhere
shipit: ${NEIGHBORS}
for i in ${SENDMAIL} princeton; do cp $$i /n/$$i/usr/local/lib/pathaliases; done
for i in ${DELIVERMAIL}; do cp $$i /n/$$i/usr/local/lib/pathaliases; $$i newaliases done
touch shipit
# reorder the output for princeton/sendmail/uubang and generate phoney costs.
princeton: down
pathalias ${ARGS} $(DEAD) -l princeton $(PATHFILES) 2>ERRORS | sort | sed 's/\(.*\) \(.*\)/\1 0 \2/' > princeton
# desperation debugging -- examine the costs.
costs:
pathalias -vci ${DEAD} -l down $(PATHFILES) > down.costs 2>ERRORS
# make one BIG file. a BIG bad idea.
cat:
cat $(PATHFILES) > CAT
# make a pathparse database. -g flag is undocumented.
edges: down
pathalias -i -g edges $(PATHFILES) >/dev/null
makedb edges down
SHAR_EOF
if test 3555 -ne "`wc -c < 'make.v8'`"
then
echo shar: error transmitting "'make.v8'" '(should have been 3555 characters)'
fi
fi
echo shar: extracting "'pathalias.1'" '(9277 characters)'
if test -f 'pathalias.1'
then
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else
cat << \SHAR_EOF > 'pathalias.1'
.\" Thanks to Alan Silverstein for help with the manual entry.
.TH PATHALIAS 1
.SH NAME
pathalias, makedb \- electronic address router
.SH SYNOPSIS
.B pathalias
[
.B \-ivc
] [
.BI \-t \0link
] [
.BI \-l \0host
] [
.BI \-d \0link
] [
.ig
.\" the -g option is for pathparse. it's not really used by pathalias.
.BI \-g \0file
] [
..
.I files
]
.PP
.B makedb
[
.B \-a
] [
.BI \-o \0dbmfile
] [
.I files ...
]
.ad b
.SH DESCRIPTION
.I pathalias
computes the shortest paths and corresponding routes from one host
(computer system) to all other known, reachable hosts.
.I pathalias
reads host-to-host connectivity
information on standard input or in the named
.IR files ,
and writes a list of
host-route pairs on the standard output.
.PP
.I makedb
takes
.I pathalias
output and creates or appends to a
.IR dbm (3)
database.
.PP
Here are the
.I pathalias
options:
.TP 6
.B \-i
Ignore case: map all host names to lower case.
By default, case is significant.
.TP
.B \-c
Print costs: print the path cost (see below) before each host-route pair.
.TP
.B \-v
Verbose: report some statistics on the standard error output.
.ig
.\" the -g option is for pathparse and is not for public consumption (yet!).
.TP
.BI \-g \0file
Dump the edges of the graph into the named file.
..
.TP
.BI \-l \0host
Set local host name to
.IR host .
By default,
.I pathalias
discovers the local host name in a system-dependent way.
.TP
.BI \-d \0arg
Declare a dead link, host, or network (see below).
If
.I arg
is of the form ``host1!host2,'' the link from host1 to host2
is treated as an extremely high cost (\fIi.e.\fP, \s-1DEAD\s0) link.
If
.I arg
is a single host name,
that host is treated as dead
and is be used as an intermediate host of last resort on any path.
If
.I arg
is a network name, the network requires a gateway.
.TP
.BR \-t \0arg
Trace input for link, host or network on the standard error output.
The form of
.I arg
is as above.
.PP
Here are the
.I makedb
options:
.TP 6
.B \-a
Append to an existing database;
by default,
.I makedb
truncates the database.
.TP
.BI \-o \0dbmfile
Identify the output file base name.
.SS \fIpathalias\fP Input Format
A line beginning with white space continues the preceding line.
Anything following `#' on an input line is ignored.
.PP
A list of host-to-host connections consists of a ``from'' host in column 1,
followed by white space,
followed by a comma-separated list of ``to' hosts, called
.IR links .
A link may be preceded or followed by a network character to use
in the route.
Valid network characters are `!' (default), `@', `:', and `%'.
A link (and network character, if present) may be
followed by a ``cost'' enclosed in parentheses.
Costs may be arbitrary
arithmetic expressions involving numbers, parentheses, `+', `\-', `*',
and `/'.
The following symbolic costs are
recognized:
.RS
.nf
.ta 10mR 15m
\s-1LOCAL\s0 25 (local-area network connection)
\s-1DEDICATED\s0 95 (high speed dedicated link)
\s-1DIRECT\s0 200 (toll-free call)
\s-1DEMAND\s0 300 (long-distance call)
\s-1HOURLY\s0 500 (hourly poll)
\s-1EVENING\s0 1800 (time restricted call)
\s-1DAILY\s0 5000 (daily poll, also called \s-1POLLED\s0)
\s-1WEEKLY\s0 30000 (irregular poll)
.fi
.RE
.PP
In addition,
.SM DEAD
is a very large number (effectively infinite),
and
.SM HIGH
and
.SM LOW
are \-5 and +5 respectively,
for baud-rate or quality bonuses/penalties.
These symbolic costs represent an imperfect measure of bandwidth,
monetary cost, and frequency of connections.
For most mail traffic, it is important to minimize the number
of intermediaries in a route,
thus,
.IR e.g. ,
.SM HOURLY
is far greater than
.SM DAILY
/ 24.
If no cost is given,
a default of 4000 is used.
.PP
For the most part, arithmetic expressions that mix symbolic constants
other than
.SM HIGH
and
.SM LOW
make no sense.
.IR E.g. ,
if a host calls a local neighbor whenever there is work,
and additionally polls every evening,
the cost is
.SM DIRECT,
.B not
.SM DIRECT+EVENING.
.PP
Some examples:
.RS
.nf
.ta 10m 15m
down princeton!(\s-1DEDICATED\s0), tilt,
%thrash(\s-1LOCAL\s0)
princeton topaz!(\s-1DEMAND\s0+\s-1LOW\s0)
topaz @rutgers(\s-1LOCAL\s0)
.fi
.RE
.PP
.fi
.RE
If a link is encountered more than once,
the least-cost occurrence dictates the cost and network character.
Links are treated as bidirectional, to the extent that a
.SM DEAD
reverse link is assumed unless better information is available.
.PP
The set of names by which a host is known by its neighbors is
called its
.IR aliases .
Aliases are declared as follows:
.RS
name = alias, alias ...
.RE
.PP
The name used in the route to or through aliased hosts
is the name by which the host is known
to its predecessor in the route.
.PP
Fully connected networks, such as the
.SM ARPANET
or a local-area network,
are declared as follows:
.RS
net = {host, host, ...}
.RE
.PP
The host-list may be preceded or followed by a routing
character, and may be followed by a cost:
.RS
.nf
princeton-ethernet = {down, up, princeton}!(\s-1LOCAL\s0)
\s-1ARPA\s0 = @{sri-unix, mit-ai, su-score}(\s-1DEDICATED\s0)
.fi
.RE
.PP
See also the sections on
.I gateways
and
.I domains
below.
.PP
Connection data may be given while hiding host names
by declaring
.RS
private {host, host, ...}
.RE
.PP
.I pathalias
will not generate routes for private hosts or for any
host with the same name as a private host, but may produce routes
through them.
The scope of a private declaration extends from the declaration to the end of
the input file in which it appears.
It is best to put private declarations at the beginning of the appropriate
input file.
.SS Output Format
A list of host-route pairs is written to the standard output,
where route is a string appropriate for use with
.IR printf (3),
.IR e.g. ,
.RS
.nf
.ta 10m 20m
rutgers princeton!topaz!%s@rutgers
.fi
.RE
.PP
The ``%s'' in the route string should be replaced by the
user name at the destination host.
(This task is normally performed by a mailer.)
.PP
Except for
.I domains
(see below),
the name of a network is never used in
expansions.
Thus, in the earlier example, the path from down to
up would be ``up!%s,'' not ``princeton-ethernet!up!%s.''
.SS Gateways
A network is represented by
a pseudo-host and a set of network members.
Links from the members to the network have the weight given in
the input, while the cost from the network to the members is zero.
If a network is declared dead on the command line (with the
.B \-d
option),
the member-to-network links are marked dead,
which discourages paths to members by way of the network.
.PP
If the input also shows a link from a host to the network,
then that host will be preferred as a gateway.
Gateways need not be network members.
.PP
.IR E.g. ,
suppose
.SM CSNET
is declared dead on the command line
and the input contains
.RS
.nf
.ta 10m 20m
\s-1CSNET\s0 = {...}
csnet-relay csnet
.fi
.RE
.PP
Then routes to
.SM CSNET
hosts will use csnet-relay as a gateway.
.PP
.I pathalias
discourages forwarding beyond dead networks.
.SS Domains
A host or network whose name begins with `.' is called
a domain.
Domains are presumed to require gateways,
.IR i.e. ,
they are \s-1DEAD\s0.
The route given by a path through a domain is similar to
that for a network, but here
the domain name is tacked onto the end of the next host.
Subdomains are permitted.
.IR E.g. ,
.RS
.nf
.ta 1i
.ta 10m 20m
harvard .\s-1EDU\s0
\&.\s-1EDU\s0 = {.\s-1BERKELEY\s0}
\&.\s-1BERKELEY\s0 ernie
.fi
.RE
yields
.RS
.nf
.ta 10m 20m
ernie ...!harvard!ernie.\s-1BERKELEY\s0.\s-1EDU\s0!%s
.fi
.RE
.PP
If a domain member is declared private, its fully qualified domain name
is shown instead.
.IR E.g. ,
if ernie is declared a
private member of .\s-1BERKELEY\s0, then the output is
.RS
.nf
.ta 10m 25m
ernie.\s-1BERKELEY\s0.\s-1EDU\s0 ...!harvard!ernie.\s-1BERKELEY\s0.\s-1EDU\s0!%s
.fi
.RE
.PP
Output is also given for the nearest gateway
to a domain or subdomain.
.IR E.g. ,
in the example above
.RS
.nf
.ta 10m 25m
\&.\s-1EDU\s0 ...!harvard!%s
\&.\s-1BERKELEY\s0.\s-1EDU\s0 ...!harvard!%s
.fi
.RE
.SS Databases
.I Makedb
builds a
.IR dbm (3)
database from the standard input or from the named
.IR files .
(\fIMakedb\fP replaces the obsolete
.B \-b
option of
.IR pathalias ,
which is no longer recognized.)
Input is expected to be sequence of
.SM ASCII
records,
each consisting of a key field and a data field separated by a single tab.
If the tab is missing, the data field is assumed to be empty.
.SH FILES ET AL.
.ta \w'/usr/local/lib/palias.{dir,pag} 'u
/usr/local/lib/palias.{dir,pag} default dbm output
.br
newsgroup mod.map likely location of some input files
.br
.IR getopt (3),
available from newsgroup mod.sources (if not in the C library).
.SH BUGS
The order of arguments is significant.
In particular,
.B \-i
and
.B \-t
should appear early.
.PP
.I pathalias
can generate hybrid (\fIi.e.\fP ambiguous) routes, which are
abhorrent and most certainly should not be given as examples
in the manual entry.
.PP
Multiple `@'s in routes are prohibited by many mailers, so
.I pathalias
resorts to the ``magic %'' rule when appropriate.
(This convention is not documented anywhere, including here.)
.PP
Domains constitute a futile attempt to defeat anarchy and otherwise
retard progress.
.SH AUTHORS
Steve Bellovin (ulysses!smb)
.br
Peter Honeyman (princeton!honey)
SHAR_EOF
if test 9277 -ne "`wc -c < 'pathalias.1'`"
then
echo shar: error transmitting "'pathalias.1'" '(should have been 9277 characters)'
fi
fi
exit 0
# End of shell archive