freebsd-skq/share/man/man5/libmap.conf.5
Matthew N. Dodd 29ade36225 Dynamic object dependency mapping: libmap.
This is an optional feature, disabled by default.

This will be useful to people testing the various POSIX threading
libraries under -CURRENT but can easily serve other needs.
2003-04-07 16:21:26 +00:00

112 lines
3.6 KiB
Groff

.\" Copyright (c) 2003 Matthew N. Dodd <winter@jurai.net>
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\" notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\" notice, this list of conditions and the following disclaimer in the
.\" documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.\" $FreeBSD$
.\"
.\" Note: The date here should be updated whenever a non-trivial
.\" change is made to the manual page.
.Dd April 7, 2003
.Dt LIBMAP.CONF 5
.Os
.Sh NAME
.Nm libmap.conf
.Nd "configuration file for dynamic object dependency mapping"
.Sh DESCRIPTION
The
.Em libmap
functionality of
.Nm ld-elf.so.1
allows dynamic object dependencies to be mapped to arbitrary
names.
.Pp
The configuration file consists of two whitespace separated columns; the
left hand side containing the mapping candidate and the right hand
side containing the mapping. Dependencies are matched against candidates
and replaced with the mappings.
.Pp
Constrained mappings may be specified by enclosing the name of the
executable or library in brackets. All mappings following a constraint
will only be evaluated for that constraint. Currently, constraints
are matched literally so that an executable with a fully qualified pathname
will only match the same constraint. This means that
.Em /usr/bin/foo
will not match a constraint for
.Em foo
and vise-versa.
.Pp
WARNING! Constrained mappings must never appear first in the configuration
file. While there is a way to specify the
.Dq default
constraint, its use is not recommended.
.Pp
The most common use at the date of writing is for allowing multiple
POSIX threading libraries to be used on a system without relinking or
changing symlinks.
.Pp
In order to enable this feature please see
.Pa src/libexec/rtld-elf/Makefile .
.Sh EXAMPLE
.Bd -literal
# /etc/libmap.conf
#
# candidate mapping
#
libc_r.so.5 libthr.so.1 # Everything uses 'libthr'
libc_r.so libthr.so
[/usr/local/bin/mplayer] # 'mplayer' uses libc_r.
libc_r.so.5 libc_r.so.5
libc_r.so libc_r.so
[mplayer]
libc_r.so.5 libc_r.so.5
libc_r.so libc_r.so
[/usr/local/sbin/httpd] # Apache uses libkse
libc_r.so.5 libkse.so.1
libc_r.so libkse.so
[httpd]
libc_r.so.5 libkse.so.1
libc_r.so libkse.so
.Ed
.Sh FILES
.Bl -tag -width ".Pa /etc/libmap.conf" -compact
.It Pa /etc/libmap.conf
The libmap configuration file.
.El
.Sh SEE ALSO
.Xr rtld 1
.Xr ldd 1
.Sh HISTORY
The
.Nm
manual page and libmap.conf functionality first appeared in
.Fx 5.1 .
.Sh AUTHORS
This
manual page was written by
.An Matthew N. Dodd <winter@jurai.net> .