Add a manual page for the ELF dynamic linker. I initially created

rtld.1 by means of a repository copy from "src/libexec/rtld-aout/rtld.1".
Then I edited it to make it (more) accurate for the ELF dynamic
linker.

2 files changed, 22 insertions, 99 deletions

diff --git a/libexec/rtld-elf/Makefile b/libexec/rtld-elf/Makefile
index 29935143..ae3174b 100644
--- a/libexec/rtld-elf/Makefile
+++ b/libexec/rtld-elf/Makefile
@@ -5,10 +5,11 @@ MAINTAINER=	jdp
 PROG=		ld-elf.so.1
 SRCS=		rtld_start.S rtld.c lockdflt.c map_object.c malloc.c \
 		xmalloc.c debug.c reloc.c
-NOMAN=		true
+MAN1=		rtld.1
 CFLAGS+=	-Wall -DFREEBSD_ELF -I${.CURDIR}/${MACHINE_ARCH} -I${.CURDIR}
 LDFLAGS+=	-nostdlib -e .rtld_start
 INSTALLFLAGS+=	-fschg -C
+MLINKS=		rtld.1 ld-elf.so.1.1
 
 .if exists(${.CURDIR}/${MACHINE_ARCH}/Makefile.inc)
 .include "${.CURDIR}/${MACHINE_ARCH}/Makefile.inc"
diff --git a/libexec/rtld-elf/rtld.1 b/libexec/rtld-elf/rtld.1
index f937321..7d5618c 100644
--- a/libexec/rtld-elf/rtld.1
+++ b/libexec/rtld-elf/rtld.1
@@ -28,25 +28,21 @@
 .\" (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
+.Dd January 28, 2000
 .Dt RTLD 1
 .Os FreeBSD
 .Sh NAME
-.Nm ld.so ,
+.Nm ld-elf.so.1 ,
 .Nm rtld
 .Nd run-time link-editor
 .Sh DESCRIPTION
 .Nm
-is a self-contained, position independent program image providing run-time
+is a self-contained shared object providing run-time
 support for loading and link-editing shared objects into a process'
-address space. It uses the data structures
-.Po
-see
-.Xr link 5
-.Pc
+address space.  It is also commonly known as the dynamic linker.
+It uses the data structures
 contained within dynamically linked programs to determine which shared
-libraries are needed and loads them at a convenient virtual address
-using the
+libraries are needed and loads them using the
 .Xr mmap 2
 system call.
 .Pp
@@ -54,54 +50,24 @@ 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.
+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.
 This is useful for C++ libraries that contain static constructors.
 .Pp
 .Nm
-is itself a shared object that is initially loaded by the startup module
-.Em crt0 .
-Since
-.Xr a.out 5
-formats do not provide easy access to the file header from within a running
-process,
-.Em crt0
-uses the special symbol
-.Va _DYNAMIC
-to determine whether a program is in fact dynamically linked or not. Whenever
-the linker
-.Xr ld 1
-has relocated this symbol to a location other than 0,
-.Em crt0
-assumes the services of
-.Nm
-are needed
-.Po
-see
-.Xr link 5
-for details
-.Pc \&.
-.Em crt0
-passes control to
-.Nm
-\&'s entry point before the program's
-.Fn main
-routine is called. Thus,
-.Nm
-can complete the link-editing process before the dynamic program calls upon
-services of any dynamic library.
+itself is loaded by the kernel together with any dynamically-linked
+program that is to be executed.  The kernel transfers control to the
+dynamic linker.  After the dynamic linker has finished loading,
+relocating, and initializing the program and its required shared
+objects, it transfers control to the entry point of the program.
 .Pp
-To quickly locate the required shared objects in the filesystem,
+To locate the required shared objects in the filesystem,
 .Nm
 may use a
 .Dq hints
-file, prepared by the
+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 \&.
+utility.
 .Pp
 .Nm
 recognizes a number of environment variables that can be used to modify
@@ -113,7 +79,8 @@ A colon separated list of directories, overriding the default search path
 for shared libraries.
 This is ignored for set-user-ID and set-group-ID programs.
 .It Ev LD_PRELOAD
-A colon separated list of shared libraries, to be linked in before any
+A list of shared libraries, separated by colons and/or white space,
+to be linked in before any
 other shared libraries.  If the directory is not specified then
 the directories specified by LD_LIBRARY_PATH will be searched first
 followed by the set of built-in standard directories.
@@ -127,38 +94,6 @@ of each function.
 .Ev LD_BIND_NOW
 increases the start-up time of a program, but it avoids run-time
 surprises caused by unexpectedly undefined functions.
-.It Ev LD_WARN_NON_PURE_CODE
-When set to a nonempty string, 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.
-.It Ev LD_SUPPRESS_WARNINGS
-When set to a nonempty string, no warning messages of any kind are
-issued. Normally, a warning is given if satisfactorily versioned
-library could not be found.
-.It Ev LD_IGNORE_MISSING_OBJECTS
-When set to a nonempty string, makes it a nonfatal condition if
-one or more required shared objects cannot be loaded.
-Loading and execution proceeds using the objects that are
-available.
-A warning is produced for each missing object, unless the environment
-variable
-.Ev LD_SUPPRESS_WARNINGS
-is set to a nonempty string.
-.Pp
-This is ignored for set-user-ID and set-group-ID programs.
-.Pp
-Missing shared objects can be ignored without errors if all the
-following conditions hold:
-.Bl -bullet
-.It
-They do not supply definitions for any required data symbols.
-.It
-No functions defined by them are called during program execution.
-.It
-The environment variable
-.Ev LD_BIND_NOW
-is unset or is set to the empty string.
-.El
 .It Ev LD_TRACE_LOADED_OBJECTS
 When set to a nonempty string, causes
 .Nm
@@ -188,8 +123,6 @@ The value of the environment variable
 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 rtld Ns 's
@@ -203,23 +136,12 @@ Additionally,
 and
 .Sy \et
 are recognized and have their usual meaning.
-.\" .It Ev LD_NO_INTERN_SEARCH
-.\" When set,
-.\" .Nm
-.\" does not process any internal search paths that were recorded in the
-.\" executable.
-.\" .It Ev LD_NOSTD_PATH
-.\" 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
-/var/run/ld.so.hints
+/var/run/ld-elf.so.hints
 .Pp
 .Sh SEE ALSO
+.Xr elf 5 ,
 .Xr ld 1 ,
-.Xr link 5 ,
 .Xr ldconfig 8
-.Sh HISTORY
-The shared library model employed first appeared in SunOS 4.0