diff options
Diffstat (limited to 'libexec')
| -rw-r--r-- | libexec/ld.so/Makefile | 3 | ||||
| -rw-r--r-- | libexec/ld.so/ld.so.8 | 173 |
2 files changed, 174 insertions, 2 deletions
diff --git a/libexec/ld.so/Makefile b/libexec/ld.so/Makefile index c30982d03a0..b4197a59b5e 100644 --- a/libexec/ld.so/Makefile +++ b/libexec/ld.so/Makefile @@ -1,9 +1,8 @@ -# $OpenBSD: Makefile,v 1.19 2003/04/17 03:40:45 drahn Exp $ +# $OpenBSD: Makefile,v 1.20 2003/06/26 17:55:42 drahn Exp $ SUBDIR=ldconfig ldd VPATH=${.CURDIR}/../../lib/libc/string:${.CURDIR}/../../sys/lib/libsa -NOMAN= SRCS= ldasm.S loader.c resolve.c dlfcn.c dl_printf.c rtld_machine.c SRCS+= util.c sod.c strsep.c strtol.c dir.c .if (${MACHINE_ARCH} == "i386") diff --git a/libexec/ld.so/ld.so.8 b/libexec/ld.so/ld.so.8 new file mode 100644 index 00000000000..7417f8228ab --- /dev/null +++ b/libexec/ld.so/ld.so.8 @@ -0,0 +1,173 @@ +.\" $OpenBSD: ld.so.8,v 1.1 2003/06/26 17:55:42 drahn Exp $ +.\" $NetBSD: rtld.1,v 1.2 1995/10/08 23:43:28 pk Exp $ +.\" +.\" Copyright (c) 1995 Paul Kranenburg +.\" 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. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by Paul Kranenburg. +.\" 3. The name of the author may not be used to endorse or promote products +.\" derived from this software without specific prior written permission +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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. +.\" +.Dd June 27, 1995 +.Dt LD.SO 1 +.Os +.Sh NAME +.Nm ld.so +.Nd run-time link-editor +.Sh DESCRIPTION +.Nm +is a self-contained, position independent program image providing run-time +support for loading and link-editing shared objects into a process's +address space. It uses the data structures +.Po +see +.Xr link 5 +.Pc +contained within dynamically linked programs to determine which shared +libraries are needed and loads them at a convenient virtual address +using the +.Xr mmap 2 +system call. +.Pp +After all shared libraries have been successfully loaded, +.Nm +proceeds to resolve external references from both the main program and +all objects loaded. A mechanism is provided for initialization routines +to be called, on a per-object basis, giving a shared object an opportunity +to perform any extra set-up, before execution of the program proper begins. + +<talk about CTORS/DTORS> + +.Pp +.Nm +is itself a shared object that is initially loaded by the the kernel +<How it is run> +.Pp +To quickly locate the required shared objects in the filesystem, +.Nm +may use a +.Dq hints +file, prepared by the +.Xr ldconfig 8 +utility, in which the full path specification of the shared objects can be +looked up by hashing on the 3-tuple +.Ao +library-name, major-version-number, minor-version-number +.Ac Ns \&. +.Pp +.Nm +recognises a number of environment variables that can be used to modify +its behaviour as follows: +.Pp +.Bl -tag -width "LD_TRACE_LOADED_OBJECTS_PROGNAME" +.It Ev LD_LIBRARY_PATH +A colon separated list of directories, overriding the default search path +for shared libraries. +This variable is ignored for set-user-ID and set-group-ID executables. +.It Ev LD_PRELOAD +A colon separate list of library names to load before any of the regular +libraries are loaded. +This variable is ignored for set-user-ID and set-group-ID executables. +.It Ev LD_WARN_NON_PURE_CODE +When set, issue a warning whenever a link-editing operation requires +modification of the text segment of some loaded object. This is usually +indicative of an incorrectly built library. +<not yet supported> +.It Ev LD_SUPPRESS_WARNINGS +When set, no warning messages of any kind are issued. Normally, a warning +is given if satisfactorily versioned library could not be found. +<not yet supported> +.It Ev LD_TRACE_LOADED_OBJECTS +When set, causes +.Nm +to exit after loading the shared objects and printing a summary which includes +the absolute pathnames of all objects, to standard output. +.It Ev LD_TRACE_LOADED_OBJECTS_FMT1 +.It Ev LD_TRACE_LOADED_OBJECTS_FMT2 +When set, these variables are interpreted as format strings a la +.Xr printf 3 +to customize the trace output and are used by +.Xr ldd 1 Ns 's +.Fl f +option and allows +.Xr ldd 1 +to be operated as a filter more conveniently. +The following conversions can be used: +.Bl -tag -indent "LD_TRACE_LOADED_OBJECTS_FMT1 " -width "xxxx" +.It \&%a +The main program's name +.Po also known as +.Dq __progname +.Pc . +.It \&%A +The value of the environment variable +.Ev LD_TRACE_LOADED_OBJECTS_PROGNAME +<not yet supported> +.It \&%o +The library name. +.It \&%m +The library's major version number. +.It \&%n +The library's minor version number. +.It \&%p +The full pathname as determined by +.Nm ld.so Ns 's +library search rules. +.It \&%x +The library's load address. +.El +.Pp +Additionally, +.Sy \en +and +.Sy \et +are recognised and have their usual meaning. +<not yet supported> +.It Ev LD_NO_INTERN_SEARCH +When set, +.Nm +does not process any internal search paths that were recorded in the +executable. +<not yet supported> +.It Ev LD_NOSTD_PATH +<not yet supported> +When set, do not include a set of built-in standard directory paths for +searching. This might be useful when running on a system with a completely +non-standard filesystem layout. +.El +.Pp +.Sh FILES +.Bl -tag -width /var/run/ld.so.hintsXXX -compact +.It Pa /var/run/ld.so.hints +library location hints built by +.Xr ldconfig 8 +.El +.Pp +.Sh SEE ALSO +.Xr ld 1 , +.Xr link 5 , +.Xr ldconfig 8 +.Sh HISTORY +The shared library model employed first appeared in SunOS 4.0. + |