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 24  .\" $Id$
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 26  .Dd August 15, 2006
 27  .Os
 28  .Dt ELF_GETARSYM 3
 29  .Sh NAME
 30  .Nm elf_getarsym
 31  .Nd retrieve the symbol table of an archive
 32  .Sh LIBRARY
 33  .Lb libelf
 34  .Sh SYNOPSIS
 35  .In libelf.h
 36  .Ft "Elf_Arsym *"
 37  .Fn elf_getarsym "Elf *elf" "size_t *ptr"
 38  .Sh DESCRIPTION
 39  The function
 40  .Fn elf_getarsym
 41  retrieves the symbol table for an
 42  .Xr ar 1
 43  archive, if one is available.
 44  .Pp
 45  Argument
 46  .Ar elf
 47  should be a descriptor for an
 48  .Xr ar 1
 49  archive opened using
 50  .Fn elf_begin
 51  or
 52  .Fn elf_memory .
 53  .Pp
 54  If the archive
 55  .Ar elf
 56  contains a symbol table with n entries, this function returns a
 57  pointer to an array of n+1
 58  .Vt Elf_Arsym
 59  structures.
 60  An
 61  .Vt Elf_Arsym
 62  structure has the following elements:
 63  .Bl -tag -width indent -compact
 64  .It Vt "char *" Va as_name
 65  This structure member is a pointer to a null-terminated symbol name.
 66  .It Vt "off_t" Va as_off
 67  This structure member contains the byte offset from the beginning of the archive to
 68  the header for the archive member.
 69  This value is suitable for use with
 70  .Xr elf_rand 3 .
 71  .It Vt "unsigned long" Va as_hash
 72  This structure member contains a portable hash value for the symbol
 73  name, as computed by
 74  .Xr elf_hash 3 .
 75  .El
 76  .Pp
 77  The last entry of the returned array will have a NULL value for member
 78  .Va as_name ,
 79  a zero value for member
 80  .Va as_off
 81  and an illegal value of ~0UL for
 82  .Va as_hash .
 83  .Pp
 84  If argument
 85  .Ar ptr
 86  is non-null, the
 87  .Fn elf_getarsym
 88  function will store the number of table entries returned (including the
 89  sentinel entry at the end) into the location it points to.
 90  .Sh RETURN VALUES
 91  Function
 92  .Fn elf_getarsym
 93  returns a pointer to an array of
 94  .Vt Elf_Arsym
 95  structures if successful, or a NULL
 96  pointer if an error was encountered.
 97  .Pp
 98  If argument
 99  .Ar ptr
100  is non-null and there was no error, the library will store the
101  number of archive symbol entries returned into the location it
102  points to.
103  If argument
104  .Ar ptr
105  is non-null and an error was encountered, the library will
106  set the location pointed to by it to zero.
107  .Sh ERRORS
108  Function
109  .Fn elf_getarsym
110  may fail with the following errors:
111  .Bl -tag -width "[ELF_E_RESOURCE]"
112  .It Bq Er ELF_E_ARGUMENT
113  Argument
114  .Ar elf
115  was NULL.
116  .It Bq Er ELF_E_ARGUMENT
117  Argument
118  .Ar elf
119  was not a descriptor for an
120  .Xr ar 1
121  archive.
122  .El
123  .Sh SEE ALSO
124  .Xr elf 3 ,
125  .Xr elf_begin 3 ,
126  .Xr elf_getarhdr 3 ,
127  .Xr elf_hash 3 ,
128  .Xr elf_memory 3 ,
129  .Xr elf_next 3 ,
130  .Xr elf_rand 3