OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [gnu-old/] [gdb-7.1/] [bfd/] [doc/] [archive.texi] - Blame information for rev 856

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 227 jeremybenn
@section Archives
2
 
3
 
4
@strong{Description}@*
5
An archive (or library) is just another BFD.  It has a symbol
6
table, although there's not much a user program will do with it.
7
 
8
The big difference between an archive BFD and an ordinary BFD
9
is that the archive doesn't have sections.  Instead it has a
10
chain of BFDs that are considered its contents.  These BFDs can
11
be manipulated like any other.  The BFDs contained in an
12
archive opened for reading will all be opened for reading.  You
13
may put either input or output BFDs into an archive opened for
14
output; they will be handled correctly when the archive is closed.
15
 
16
Use @code{bfd_openr_next_archived_file} to step through
17
the contents of an archive opened for input.  You don't
18
have to read the entire archive if you don't want
19
to!  Read it until you find what you want.
20
 
21
Archive contents of output BFDs are chained through the
22
@code{next} pointer in a BFD.  The first one is findable through
23
the @code{archive_head} slot of the archive.  Set it with
24
@code{bfd_set_archive_head} (q.v.).  A given BFD may be in only one
25
open output archive at a time.
26
 
27
As expected, the BFD archive code is more general than the
28
archive code of any given environment.  BFD archives may
29
contain files of different formats (e.g., a.out and coff) and
30
even different architectures.  You may even place archives
31
recursively into archives!
32
 
33
This can cause unexpected confusion, since some archive
34
formats are more expressive than others.  For instance, Intel
35
COFF archives can preserve long filenames; SunOS a.out archives
36
cannot.  If you move a file from the first to the second
37
format and back again, the filename may be truncated.
38
Likewise, different a.out environments have different
39
conventions as to how they truncate filenames, whether they
40
preserve directory names in filenames, etc.  When
41
interoperating with native tools, be sure your files are
42
homogeneous.
43
 
44
Beware: most of these formats do not react well to the
45
presence of spaces in filenames.  We do the best we can, but
46
can't always handle this case due to restrictions in the format of
47
archives.  Many Unix utilities are braindead in regards to
48
spaces and such in filenames anyway, so this shouldn't be much
49
of a restriction.
50
 
51
Archives are supported in BFD in @code{archive.c}.
52
 
53
@subsection Archive functions
54
 
55
 
56
@findex bfd_get_next_mapent
57
@subsubsection @code{bfd_get_next_mapent}
58
@strong{Synopsis}
59
@example
60
symindex bfd_get_next_mapent
61
   (bfd *abfd, symindex previous, carsym **sym);
62
@end example
63
@strong{Description}@*
64
Step through archive @var{abfd}'s symbol table (if it
65
has one).  Successively update @var{sym} with the next symbol's
66
information, returning that symbol's (internal) index into the
67
symbol table.
68
 
69
Supply @code{BFD_NO_MORE_SYMBOLS} as the @var{previous} entry to get
70
the first one; returns @code{BFD_NO_MORE_SYMBOLS} when you've already
71
got the last one.
72
 
73
A @code{carsym} is a canonical archive symbol.  The only
74
user-visible element is its name, a null-terminated string.
75
 
76
@findex bfd_set_archive_head
77
@subsubsection @code{bfd_set_archive_head}
78
@strong{Synopsis}
79
@example
80
bfd_boolean bfd_set_archive_head (bfd *output, bfd *new_head);
81
@end example
82
@strong{Description}@*
83
Set the head of the chain of
84
BFDs contained in the archive @var{output} to @var{new_head}.
85
 
86
@findex bfd_openr_next_archived_file
87
@subsubsection @code{bfd_openr_next_archived_file}
88
@strong{Synopsis}
89
@example
90
bfd *bfd_openr_next_archived_file (bfd *archive, bfd *previous);
91
@end example
92
@strong{Description}@*
93
Provided a BFD, @var{archive}, containing an archive and NULL, open
94
an input BFD on the first contained element and returns that.
95
Subsequent calls should pass
96
the archive and the previous return value to return a created
97
BFD to the next contained element. NULL is returned when there
98
are no more.
99
 

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.