.\"	$NetBSD: elf_getarsym.3,v 1.1.1.1 2009/12/19 05:43:39 thorpej Exp $
.\"
.\" Copyright (c) 2006 Joseph Koshy.  All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
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.\"    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.
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.\" This software is provided by Joseph Koshy ``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 Joseph Koshy 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
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.\" $FreeBSD: src/lib/libelf/elf_getarsym.3,v 1.2.10.1.2.1 2009/10/25 01:10:29 kensmith Exp $
.\"
.Dd August 15, 2006
.Os
.Dt ELF_GETARSYM 3
.Sh NAME
.Nm elf_getarsym
.Nd retrieve the symbol table of an archive
.Sh LIBRARY
.Lb libelf
.Sh SYNOPSIS
.In libelf.h
.Ft "Elf_Arsym *"
.Fn elf_getarsym "Elf *elf" "size_t *ptr"
.Sh DESCRIPTION
The function
.Fn elf_getarsym
retrieves the symbol table for an
.Xr ar 1
archive, if one is available.
.Pp
Argument
.Ar elf
should be a descriptor for an
.Xr ar 1
archive opened using
.Fn elf_begin
or
.Fn elf_memory .
.Pp
If the archive
.Ar elf
contains a symbol table with n entries, this function returns a
pointer to an array of n+1
.Vt Elf_Arsym
structures.
An
.Vt Elf_Arsym
structure has the following elements:
.Bl -tag -width indent -compact
.It Vt "char *" Va as_name
This structure member is a pointer to a null-terminated symbol name.
.It Vt "off_t" Va as_off
This structure member contains the byte offset from the beginning of the archive to
the header for the archive member.
This value is suitable for use with
.Xr elf_rand 3 .
.It Vt "unsigned long" Va as_hash
This structure member contains a portable hash value for the symbol
name, as computed by
.Xr elf_hash 3 .
.El
.Pp
The last entry of the returned array will have a NULL value for member
.Va as_name ,
a zero value for member
.Va as_off
and an illegal value of ~0UL for
.Va as_hash .
.Pp
If argument
.Ar ptr
is non-null, the
.Fn elf_getarsym
function will store the number of table entries returned (including the
sentinel entry at the end) into the location it points to.
.Sh RETURN VALUES
Function
.Fn elf_getarsym
returns a pointer to an array of
.Vt Elf_Arsym
structures if successful, or a NULL
pointer if an error was encountered.
.Pp
If argument
.Ar ptr
is non-null and there was no error, the library will store the
number of archive symbol entries returned into the location it
points to.
If argument
.Ar ptr
is non-null and an error was encountered, the library will
set the location pointed to by it to zero.
.Sh ERRORS
Function
.Fn elf_getarsym
may fail with the following errors:
.Bl -tag -width "[ELF_E_RESOURCE]"
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar elf
was NULL.
.It Bq Er ELF_E_ARGUMENT
Argument
.Ar elf
was not a descriptor for an
.Xr ar 1
archive.
.El
.Sh SEE ALSO
.Xr elf 3 ,
.Xr elf_begin 3 ,
.Xr elf_getarhdr 3 ,
.Xr elf_hash 3 ,
.Xr elf_memory 3 ,
.Xr elf_next 3 ,
.Xr elf_rand 3