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66 lines
2.0 KiB
Plaintext
66 lines
2.0 KiB
Plaintext
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@section File caching
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The file caching mechanism is embedded within BFD and allows
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the application to open as many BFDs as it wants without
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regard to the underlying operating system's file descriptor
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limit (often as low as 20 open files). The module in
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@code{cache.c} maintains a least recently used list of
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@code{BFD_CACHE_MAX_OPEN} files, and exports the name
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@code{bfd_cache_lookup}, which runs around and makes sure that
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the required BFD is open. If not, then it chooses a file to
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close, closes it and opens the one wanted, returning its file
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handle.
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@subsection Caching functions
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@findex bfd_cache_init
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@subsubsection @code{bfd_cache_init}
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@strong{Synopsis}
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@example
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bfd_boolean bfd_cache_init (bfd *abfd);
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@end example
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@strong{Description}@*
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Add a newly opened BFD to the cache.
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@findex bfd_cache_close
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@subsubsection @code{bfd_cache_close}
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@strong{Synopsis}
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@example
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bfd_boolean bfd_cache_close (bfd *abfd);
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@end example
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@strong{Description}@*
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Remove the BFD @var{abfd} from the cache. If the attached file is open,
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then close it too.
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@strong{Returns}@*
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@code{FALSE} is returned if closing the file fails, @code{TRUE} is
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returned if all is well.
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@findex bfd_cache_close_all
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@subsubsection @code{bfd_cache_close_all}
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@strong{Synopsis}
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@example
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bfd_boolean bfd_cache_close_all (void);
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@end example
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@strong{Description}@*
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Remove all BFDs from the cache. If the attached file is open,
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then close it too.
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@strong{Returns}@*
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@code{FALSE} is returned if closing one of the file fails, @code{TRUE} is
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returned if all is well.
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@findex bfd_open_file
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@subsubsection @code{bfd_open_file}
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@strong{Synopsis}
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@example
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FILE* bfd_open_file (bfd *abfd);
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@end example
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@strong{Description}@*
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Call the OS to open a file for @var{abfd}. Return the @code{FILE *}
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(possibly @code{NULL}) that results from this operation. Set up the
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BFD so that future accesses know the file is open. If the @code{FILE *}
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returned is @code{NULL}, then it won't have been put in the
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cache, so it won't have to be removed from it.
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