.\"	$NetBSD: ld.so.conf.5,v 1.20.38.1 2019/09/02 16:39:21 martin Exp $
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.\" Copyright (c) 1996 Matthew R. Green
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.Dd July 21, 2004
.Dt LD.SO.CONF 5
.Os
.Sh NAME
.Nm ld.so.conf
.Nd run-time link-editor configuration file
.Sh DESCRIPTION
The
.Nm
file specifies additional default directories (beyond the standard set,
normally
.Dq Pa /usr/lib ) .
.Pp
On
.Xr a.out 5
systems, this file is scanned by
.Xr ldconfig 8
to create the hints files used by the run-time linker
.Pa /usr/libexec/ld.so
to locate shared libraries.
.Pp
On
.Xr elf 5
systems, this file is scanned directly by the run-time linker
.Pa /usr/libexec/ld.elf_so .
.Pp
Lines beginning with
.Sq #
are treated as comments and ignored.
Any other non-blank lines beginning
with
.Sq /
are stripped of leading whitespace and trailing comments
(introduced with
.Sq # )
together with any preceding whitespace, then treated as directories to be
scanned for shared libraries to add to the hints.
.Pp
On
.Xr elf 5
lines that do not begin with a
.Sq /
are parsed as hardware dependent per
library directives:
.Bd -literal
<library> <sysctl> <variable>[,...]:<library>[,...] ...
.Ed
.Pp
If there is no match, the standard action is taken.
.Sh FILES
.Pa /etc/ld.so.conf
.Sh EXAMPLES
.Bd -literal
libm.so.0	machdep.fpu_present	1:libm387.so.0,libm.so.0
.Ed
.Pp
The above line loads both libm387 and libm when the
.Xr sysctl 3
variable fpu_present has the value 1.
.Sh SEE ALSO
.Xr ld.aout_so 1 ,
.Xr ld.elf_so 1 ,
.Xr a.out 5 ,
.Xr elf 5 ,
.Xr ldconfig 8
.Sh HISTORY
The
.Nm
file appeared in
.Nx 1.3 .
The ELF support for it was added in
.Nx 1.5 .
.Sh BUGS
Directory names containing the comment character
.Pq Sq #
and/or leading or trailing whitespace cannot be included.
(Embedded blanks are allowed, however.)