NetBSD/usr.bin/ldd/ldd.1

.\"	$NetBSD: ldd.1,v 1.13 2004/05/23 06:51:42 skrll Exp $
.\"
.\" Copyright (c) 1998 The NetBSD Foundation, Inc.
.\" All rights reserved.
.\"
.\" This code is derived from software contributed to The NetBSD Foundation
.\" by Paul Kranenburg.
.\"
.\" 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 the NetBSD
.\"        Foundation, Inc. and its contributors.
.\" 4. Neither the name of The NetBSD Foundation nor the names of its
.\"    contributors may be used to endorse or promote products derived
.\"    from this software without specific prior written permission.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
.\"
.Dd May 23, 2004
.Dt LDD 1
.Os
.Sh NAME
.Nm ldd
.Nd list dynamic object dependencies
.Sh SYNOPSIS
.Nm
.Op Fl f Ar format
.Ar program ...
.Sh DESCRIPTION
.Nm
displays all shared objects that are needed to run the given program.
Contrary to
.Xr nm 1 ,
the list includes
.Dq indirect
dependencies that are the result of needed shared objects which themselves
depend on yet other shared objects.
Zero, one or two
.Fl f
options may be given. The argument is a format string passed to
.Xr rtld 1
and allows customization of
.Nm ldd Ns 's
output.
The first format argument is used for library objects and is equivalent
to the
.Xr ld.aout_so 1
environment variable
.Ev LD_TRACE_LOADED_OBJECTS_FMT1 .
It defaults to
.Qq "\et-l%o.%m =\*[Gt] %p\en"
for elf and
.Qq "\et-l%o.%m =\*[Gt] %p (%x)\en"
for a.out.
The second format argument is used for non-library objects and it is equivalent
to the
.Xr ld.aout_so 1
environment variable
.Ev LD_TRACE_LOADED_OBJECTS_FMT2 .
It defaults to
.Qq "\et%o =\*[Gt] %p\en"
for elf and
.Qq "\et%o (%x)\en"
for a.out.
.Pp
These arguments are interpreted as format strings a la
.Xr printf 3
to customize the trace output and allow
.Nm
to be operated as a filter more conveniently.
The following conversions can be used:
.Bl -tag -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
in a.out and the program name from the argument vector from elf.
.It \&%o
The library name.
.It \&%m
The library's major version number.
.It \&%n
The library's minor version number (a.out only, ignored in elf).
.It \&%p
The full pathname as determined by
.Nm rtld Ns 's
library search rules.
.It \&%x
The library's load address
.El
.Pp
Additionally,
.Sy \en
and
.Sy \et
are recognized and have their usual meaning.
.Sh SEE ALSO
.Xr ld 1 ,
.Xr ld.aout_so 1 ,
.Xr ld.elf_so 1 ,
.Xr nm 1 ,
.Xr rtld 1
.Sh HISTORY
A
.Nm
utility first appeared in SunOS 4.0, it appeared in its current form
in
.Nx 0.9a .
.Sh BUGS
The
a.out
.Nm
actually runs the program it has been requested to analyze which in specially
constructed environments can have security implications.