1@section File caching
2The file caching mechanism is embedded within BFD and allows
3the application to open as many BFDs as it wants without
4regard to the underlying operating system's file descriptor
5limit (often as low as 20 open files).  The module in
6@code{cache.c} maintains a least recently used list of
7@code{BFD_CACHE_MAX_OPEN} files, and exports the name
8@code{bfd_cache_lookup}, which runs around and makes sure that
9the required BFD is open. If not, then it chooses a file to
10close, closes it and opens the one wanted, returning its file
11handle.
12
13@subsection Caching functions
14
15
16@findex bfd_cache_init
17@subsubsection @code{bfd_cache_init}
18@strong{Synopsis}
19@example
20bfd_boolean bfd_cache_init (bfd *abfd);
21@end example
22@strong{Description}@*
23Add a newly opened BFD to the cache.
24
25@findex bfd_cache_close
26@subsubsection @code{bfd_cache_close}
27@strong{Synopsis}
28@example
29bfd_boolean bfd_cache_close (bfd *abfd);
30@end example
31@strong{Description}@*
32Remove the BFD @var{abfd} from the cache. If the attached file is open,
33then close it too.
34
35@strong{Returns}@*
36@code{FALSE} is returned if closing the file fails, @code{TRUE} is
37returned if all is well.
38
39@findex bfd_cache_close_all
40@subsubsection @code{bfd_cache_close_all}
41@strong{Synopsis}
42@example
43bfd_boolean bfd_cache_close_all (void);
44@end example
45@strong{Description}@*
46Remove all BFDs from the cache. If the attached file is open,
47then close it too.
48
49@strong{Returns}@*
50@code{FALSE} is returned if closing one of the file fails, @code{TRUE} is
51returned if all is well.
52
53@findex bfd_open_file
54@subsubsection @code{bfd_open_file}
55@strong{Synopsis}
56@example
57FILE* bfd_open_file (bfd *abfd);
58@end example
59@strong{Description}@*
60Call the OS to open a file for @var{abfd}.  Return the @code{FILE *}
61(possibly @code{NULL}) that results from this operation.  Set up the
62BFD so that future accesses know the file is open. If the @code{FILE *}
63returned is @code{NULL}, then it won't have been put in the
64cache, so it won't have to be removed from it.
65
66