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+@section Targets
+
+
+@strong{Description}@*
+Each port of BFD to a different machine requires the creation
+of a target back end. All the back end provides to the root
+part of BFD is a structure containing pointers to functions
+which perform certain low level operations on files. BFD
+translates the applications's requests through a pointer into
+calls to the back end routines.
+
+When a file is opened with @code{bfd_openr}, its format and
+target are unknown. BFD uses various mechanisms to determine
+how to interpret the file. The operations performed are:
+
+@itemize @bullet
+
+@item
+Create a BFD by calling the internal routine
+@code{_bfd_new_bfd}, then call @code{bfd_find_target} with the
+target string supplied to @code{bfd_openr} and the new BFD pointer.
+
+@item
+If a null target string was provided to @code{bfd_find_target},
+look up the environment variable @code{GNUTARGET} and use
+that as the target string.
+
+@item
+If the target string is still @code{NULL}, or the target string is
+@code{default}, then use the first item in the target vector
+as the target type, and set @code{target_defaulted} in the BFD to
+cause @code{bfd_check_format} to loop through all the targets.
+@xref{bfd_target}. @xref{Formats}.
+
+@item
+Otherwise, inspect the elements in the target vector
+one by one, until a match on target name is found. When found,
+use it.
+
+@item
+Otherwise return the error @code{bfd_error_invalid_target} to
+@code{bfd_openr}.
+
+@item
+@code{bfd_openr} attempts to open the file using
+@code{bfd_open_file}, and returns the BFD.
+@end itemize
+Once the BFD has been opened and the target selected, the file
+format may be determined. This is done by calling
+@code{bfd_check_format} on the BFD with a suggested format.
+If @code{target_defaulted} has been set, each possible target
+type is tried to see if it recognizes the specified format.
+@code{bfd_check_format} returns @code{TRUE} when the caller guesses right.
+@menu
+* bfd_target::
+@end menu
+
+@node bfd_target, , Targets, Targets
+
+@subsection bfd_target
+
+
+@strong{Description}@*
+This structure contains everything that BFD knows about a
+target. It includes things like its byte order, name, and which
+routines to call to do various operations.
+
+Every BFD points to a target structure with its @code{xvec}
+member.
+
+The macros below are used to dispatch to functions through the
+@code{bfd_target} vector. They are used in a number of macros further
+down in @file{bfd.h}, and are also used when calling various
+routines by hand inside the BFD implementation. The @var{arglist}
+argument must be parenthesized; it contains all the arguments
+to the called function.
+
+They make the documentation (more) unpleasant to read, so if
+someone wants to fix this and not break the above, please do.
+@example
+#define BFD_SEND(bfd, message, arglist) \
+ ((*((bfd)->xvec->message)) arglist)
+
+#ifdef DEBUG_BFD_SEND
+#undef BFD_SEND
+#define BFD_SEND(bfd, message, arglist) \
+ (((bfd) && (bfd)->xvec && (bfd)->xvec->message) ? \
+ ((*((bfd)->xvec->message)) arglist) : \
+ (bfd_assert (__FILE__,__LINE__), NULL))
+#endif
+@end example
+For operations which index on the BFD format:
+@example
+#define BFD_SEND_FMT(bfd, message, arglist) \
+ (((bfd)->xvec->message[(int) ((bfd)->format)]) arglist)
+
+#ifdef DEBUG_BFD_SEND
+#undef BFD_SEND_FMT
+#define BFD_SEND_FMT(bfd, message, arglist) \
+ (((bfd) && (bfd)->xvec && (bfd)->xvec->message) ? \
+ (((bfd)->xvec->message[(int) ((bfd)->format)]) arglist) : \
+ (bfd_assert (__FILE__,__LINE__), NULL))
+#endif
+
+@end example
+This is the structure which defines the type of BFD this is. The
+@code{xvec} member of the struct @code{bfd} itself points here. Each
+module that implements access to a different target under BFD,
+defines one of these.
+
+FIXME, these names should be rationalised with the names of
+the entry points which call them. Too bad we can't have one
+macro to define them both!
+@example
+enum bfd_flavour
+@{
+ bfd_target_unknown_flavour,
+ bfd_target_aout_flavour,
+ bfd_target_coff_flavour,
+ bfd_target_ecoff_flavour,
+ bfd_target_xcoff_flavour,
+ bfd_target_elf_flavour,
+ bfd_target_ieee_flavour,
+ bfd_target_nlm_flavour,
+ bfd_target_oasys_flavour,
+ bfd_target_tekhex_flavour,
+ bfd_target_srec_flavour,
+ bfd_target_verilog_flavour,
+ bfd_target_ihex_flavour,
+ bfd_target_som_flavour,
+ bfd_target_os9k_flavour,
+ bfd_target_versados_flavour,
+ bfd_target_msdos_flavour,
+ bfd_target_ovax_flavour,
+ bfd_target_evax_flavour,
+ bfd_target_mmo_flavour,
+ bfd_target_mach_o_flavour,
+ bfd_target_pef_flavour,
+ bfd_target_pef_xlib_flavour,
+ bfd_target_sym_flavour
+@};
+
+enum bfd_endian @{ BFD_ENDIAN_BIG, BFD_ENDIAN_LITTLE, BFD_ENDIAN_UNKNOWN @};
+
+/* Forward declaration. */
+typedef struct bfd_link_info _bfd_link_info;
+
+typedef struct bfd_target
+@{
+ /* Identifies the kind of target, e.g., SunOS4, Ultrix, etc. */
+ char *name;
+
+ /* The "flavour" of a back end is a general indication about
+ the contents of a file. */
+ enum bfd_flavour flavour;
+
+ /* The order of bytes within the data area of a file. */
+ enum bfd_endian byteorder;
+
+ /* The order of bytes within the header parts of a file. */
+ enum bfd_endian header_byteorder;
+
+ /* A mask of all the flags which an executable may have set -
+ from the set @code{BFD_NO_FLAGS}, @code{HAS_RELOC}, ...@code{D_PAGED}. */
+ flagword object_flags;
+
+ /* A mask of all the flags which a section may have set - from
+ the set @code{SEC_NO_FLAGS}, @code{SEC_ALLOC}, ...@code{SET_NEVER_LOAD}. */
+ flagword section_flags;
+
+ /* The character normally found at the front of a symbol.
+ (if any), perhaps `_'. */
+ char symbol_leading_char;
+
+ /* The pad character for file names within an archive header. */
+ char ar_pad_char;
+
+ /* The maximum number of characters in an archive header. */
+ unsigned short ar_max_namelen;
+
+ /* Entries for byte swapping for data. These are different from the
+ other entry points, since they don't take a BFD as the first argument.
+ Certain other handlers could do the same. */
+ bfd_uint64_t (*bfd_getx64) (const void *);
+ bfd_int64_t (*bfd_getx_signed_64) (const void *);
+ void (*bfd_putx64) (bfd_uint64_t, void *);
+ bfd_vma (*bfd_getx32) (const void *);
+ bfd_signed_vma (*bfd_getx_signed_32) (const void *);
+ void (*bfd_putx32) (bfd_vma, void *);
+ bfd_vma (*bfd_getx16) (const void *);
+ bfd_signed_vma (*bfd_getx_signed_16) (const void *);
+ void (*bfd_putx16) (bfd_vma, void *);
+
+ /* Byte swapping for the headers. */
+ bfd_uint64_t (*bfd_h_getx64) (const void *);
+ bfd_int64_t (*bfd_h_getx_signed_64) (const void *);
+ void (*bfd_h_putx64) (bfd_uint64_t, void *);
+ bfd_vma (*bfd_h_getx32) (const void *);
+ bfd_signed_vma (*bfd_h_getx_signed_32) (const void *);
+ void (*bfd_h_putx32) (bfd_vma, void *);
+ bfd_vma (*bfd_h_getx16) (const void *);
+ bfd_signed_vma (*bfd_h_getx_signed_16) (const void *);
+ void (*bfd_h_putx16) (bfd_vma, void *);
+
+ /* Format dependent routines: these are vectors of entry points
+ within the target vector structure, one for each format to check. */
+
+ /* Check the format of a file being read. Return a @code{bfd_target *} or zero. */
+ const struct bfd_target *(*_bfd_check_format[bfd_type_end]) (bfd *);
+
+ /* Set the format of a file being written. */
+ bfd_boolean (*_bfd_set_format[bfd_type_end]) (bfd *);
+
+ /* Write cached information into a file being written, at @code{bfd_close}. */
+ bfd_boolean (*_bfd_write_contents[bfd_type_end]) (bfd *);
+
+@end example
+The general target vector. These vectors are initialized using the
+BFD_JUMP_TABLE macros.
+@example
+
+ /* Generic entry points. */
+#define BFD_JUMP_TABLE_GENERIC(NAME) \
+ NAME##_close_and_cleanup, \
+ NAME##_bfd_free_cached_info, \
+ NAME##_new_section_hook, \
+ NAME##_get_section_contents, \
+ NAME##_get_section_contents_in_window
+
+ /* Called when the BFD is being closed to do any necessary cleanup. */
+ bfd_boolean (*_close_and_cleanup) (bfd *);
+ /* Ask the BFD to free all cached information. */
+ bfd_boolean (*_bfd_free_cached_info) (bfd *);
+ /* Called when a new section is created. */
+ bfd_boolean (*_new_section_hook) (bfd *, sec_ptr);
+ /* Read the contents of a section. */
+ bfd_boolean (*_bfd_get_section_contents)
+ (bfd *, sec_ptr, void *, file_ptr, bfd_size_type);
+ bfd_boolean (*_bfd_get_section_contents_in_window)
+ (bfd *, sec_ptr, bfd_window *, file_ptr, bfd_size_type);
+
+ /* Entry points to copy private data. */
+#define BFD_JUMP_TABLE_COPY(NAME) \
+ NAME##_bfd_copy_private_bfd_data, \
+ NAME##_bfd_merge_private_bfd_data, \
+ _bfd_generic_init_private_section_data, \
+ NAME##_bfd_copy_private_section_data, \
+ NAME##_bfd_copy_private_symbol_data, \
+ NAME##_bfd_copy_private_header_data, \
+ NAME##_bfd_set_private_flags, \
+ NAME##_bfd_print_private_bfd_data
+
+ /* Called to copy BFD general private data from one object file
+ to another. */
+ bfd_boolean (*_bfd_copy_private_bfd_data) (bfd *, bfd *);
+ /* Called to merge BFD general private data from one object file
+ to a common output file when linking. */
+ bfd_boolean (*_bfd_merge_private_bfd_data) (bfd *, bfd *);
+ /* Called to initialize BFD private section data from one object file
+ to another. */
+#define bfd_init_private_section_data(ibfd, isec, obfd, osec, link_info) \
+ BFD_SEND (obfd, _bfd_init_private_section_data, (ibfd, isec, obfd, osec, link_info))
+ bfd_boolean (*_bfd_init_private_section_data)
+ (bfd *, sec_ptr, bfd *, sec_ptr, struct bfd_link_info *);
+ /* Called to copy BFD private section data from one object file
+ to another. */
+ bfd_boolean (*_bfd_copy_private_section_data)
+ (bfd *, sec_ptr, bfd *, sec_ptr);
+ /* Called to copy BFD private symbol data from one symbol
+ to another. */
+ bfd_boolean (*_bfd_copy_private_symbol_data)
+ (bfd *, asymbol *, bfd *, asymbol *);
+ /* Called to copy BFD private header data from one object file
+ to another. */
+ bfd_boolean (*_bfd_copy_private_header_data)
+ (bfd *, bfd *);
+ /* Called to set private backend flags. */
+ bfd_boolean (*_bfd_set_private_flags) (bfd *, flagword);
+
+ /* Called to print private BFD data. */
+ bfd_boolean (*_bfd_print_private_bfd_data) (bfd *, void *);
+
+ /* Core file entry points. */
+#define BFD_JUMP_TABLE_CORE(NAME) \
+ NAME##_core_file_failing_command, \
+ NAME##_core_file_failing_signal, \
+ NAME##_core_file_matches_executable_p, \
+ NAME##_core_file_pid
+
+ char * (*_core_file_failing_command) (bfd *);
+ int (*_core_file_failing_signal) (bfd *);
+ bfd_boolean (*_core_file_matches_executable_p) (bfd *, bfd *);
+ int (*_core_file_pid) (bfd *);
+
+ /* Archive entry points. */
+#define BFD_JUMP_TABLE_ARCHIVE(NAME) \
+ NAME##_slurp_armap, \
+ NAME##_slurp_extended_name_table, \
+ NAME##_construct_extended_name_table, \
+ NAME##_truncate_arname, \
+ NAME##_write_armap, \
+ NAME##_read_ar_hdr, \
+ NAME##_write_ar_hdr, \
+ NAME##_openr_next_archived_file, \
+ NAME##_get_elt_at_index, \
+ NAME##_generic_stat_arch_elt, \
+ NAME##_update_armap_timestamp
+
+ bfd_boolean (*_bfd_slurp_armap) (bfd *);
+ bfd_boolean (*_bfd_slurp_extended_name_table) (bfd *);
+ bfd_boolean (*_bfd_construct_extended_name_table)
+ (bfd *, char **, bfd_size_type *, const char **);
+ void (*_bfd_truncate_arname) (bfd *, const char *, char *);
+ bfd_boolean (*write_armap)
+ (bfd *, unsigned int, struct orl *, unsigned int, int);
+ void * (*_bfd_read_ar_hdr_fn) (bfd *);
+ bfd_boolean (*_bfd_write_ar_hdr_fn) (bfd *, bfd *);
+ bfd * (*openr_next_archived_file) (bfd *, bfd *);
+#define bfd_get_elt_at_index(b,i) BFD_SEND (b, _bfd_get_elt_at_index, (b,i))
+ bfd * (*_bfd_get_elt_at_index) (bfd *, symindex);
+ int (*_bfd_stat_arch_elt) (bfd *, struct stat *);
+ bfd_boolean (*_bfd_update_armap_timestamp) (bfd *);
+
+ /* Entry points used for symbols. */
+#define BFD_JUMP_TABLE_SYMBOLS(NAME) \
+ NAME##_get_symtab_upper_bound, \
+ NAME##_canonicalize_symtab, \
+ NAME##_make_empty_symbol, \
+ NAME##_print_symbol, \
+ NAME##_get_symbol_info, \
+ NAME##_bfd_is_local_label_name, \
+ NAME##_bfd_is_target_special_symbol, \
+ NAME##_get_lineno, \
+ NAME##_find_nearest_line, \
+ _bfd_generic_find_line, \
+ NAME##_find_inliner_info, \
+ NAME##_bfd_make_debug_symbol, \
+ NAME##_read_minisymbols, \
+ NAME##_minisymbol_to_symbol
+
+ long (*_bfd_get_symtab_upper_bound) (bfd *);
+ long (*_bfd_canonicalize_symtab)
+ (bfd *, struct bfd_symbol **);
+ struct bfd_symbol *
+ (*_bfd_make_empty_symbol) (bfd *);
+ void (*_bfd_print_symbol)
+ (bfd *, void *, struct bfd_symbol *, bfd_print_symbol_type);
+#define bfd_print_symbol(b,p,s,e) BFD_SEND (b, _bfd_print_symbol, (b,p,s,e))
+ void (*_bfd_get_symbol_info)
+ (bfd *, struct bfd_symbol *, symbol_info *);
+#define bfd_get_symbol_info(b,p,e) BFD_SEND (b, _bfd_get_symbol_info, (b,p,e))
+ bfd_boolean (*_bfd_is_local_label_name) (bfd *, const char *);
+ bfd_boolean (*_bfd_is_target_special_symbol) (bfd *, asymbol *);
+ alent * (*_get_lineno) (bfd *, struct bfd_symbol *);
+ bfd_boolean (*_bfd_find_nearest_line)
+ (bfd *, struct bfd_section *, struct bfd_symbol **, bfd_vma,
+ const char **, const char **, unsigned int *);
+ bfd_boolean (*_bfd_find_line)
+ (bfd *, struct bfd_symbol **, struct bfd_symbol *,
+ const char **, unsigned int *);
+ bfd_boolean (*_bfd_find_inliner_info)
+ (bfd *, const char **, const char **, unsigned int *);
+ /* Back-door to allow format-aware applications to create debug symbols
+ while using BFD for everything else. Currently used by the assembler
+ when creating COFF files. */
+ asymbol * (*_bfd_make_debug_symbol)
+ (bfd *, void *, unsigned long size);
+#define bfd_read_minisymbols(b, d, m, s) \
+ BFD_SEND (b, _read_minisymbols, (b, d, m, s))
+ long (*_read_minisymbols)
+ (bfd *, bfd_boolean, void **, unsigned int *);
+#define bfd_minisymbol_to_symbol(b, d, m, f) \
+ BFD_SEND (b, _minisymbol_to_symbol, (b, d, m, f))
+ asymbol * (*_minisymbol_to_symbol)
+ (bfd *, bfd_boolean, const void *, asymbol *);
+
+ /* Routines for relocs. */
+#define BFD_JUMP_TABLE_RELOCS(NAME) \
+ NAME##_get_reloc_upper_bound, \
+ NAME##_canonicalize_reloc, \
+ NAME##_bfd_reloc_type_lookup, \
+ NAME##_bfd_reloc_name_lookup
+
+ long (*_get_reloc_upper_bound) (bfd *, sec_ptr);
+ long (*_bfd_canonicalize_reloc)
+ (bfd *, sec_ptr, arelent **, struct bfd_symbol **);
+ /* See documentation on reloc types. */
+ reloc_howto_type *
+ (*reloc_type_lookup) (bfd *, bfd_reloc_code_real_type);
+ reloc_howto_type *
+ (*reloc_name_lookup) (bfd *, const char *);
+
+
+ /* Routines used when writing an object file. */
+#define BFD_JUMP_TABLE_WRITE(NAME) \
+ NAME##_set_arch_mach, \
+ NAME##_set_section_contents
+
+ bfd_boolean (*_bfd_set_arch_mach)
+ (bfd *, enum bfd_architecture, unsigned long);
+ bfd_boolean (*_bfd_set_section_contents)
+ (bfd *, sec_ptr, const void *, file_ptr, bfd_size_type);
+
+ /* Routines used by the linker. */
+#define BFD_JUMP_TABLE_LINK(NAME) \
+ NAME##_sizeof_headers, \
+ NAME##_bfd_get_relocated_section_contents, \
+ NAME##_bfd_relax_section, \
+ NAME##_bfd_link_hash_table_create, \
+ NAME##_bfd_link_hash_table_free, \
+ NAME##_bfd_link_add_symbols, \
+ NAME##_bfd_link_just_syms, \
+ NAME##_bfd_copy_link_hash_symbol_type, \
+ NAME##_bfd_final_link, \
+ NAME##_bfd_link_split_section, \
+ NAME##_bfd_gc_sections, \
+ NAME##_bfd_merge_sections, \
+ NAME##_bfd_is_group_section, \
+ NAME##_bfd_discard_group, \
+ NAME##_section_already_linked, \
+ NAME##_bfd_define_common_symbol
+
+ int (*_bfd_sizeof_headers) (bfd *, struct bfd_link_info *);
+ bfd_byte * (*_bfd_get_relocated_section_contents)
+ (bfd *, struct bfd_link_info *, struct bfd_link_order *,
+ bfd_byte *, bfd_boolean, struct bfd_symbol **);
+
+ bfd_boolean (*_bfd_relax_section)
+ (bfd *, struct bfd_section *, struct bfd_link_info *, bfd_boolean *);
+
+ /* Create a hash table for the linker. Different backends store
+ different information in this table. */
+ struct bfd_link_hash_table *
+ (*_bfd_link_hash_table_create) (bfd *);
+
+ /* Release the memory associated with the linker hash table. */
+ void (*_bfd_link_hash_table_free) (struct bfd_link_hash_table *);
+
+ /* Add symbols from this object file into the hash table. */
+ bfd_boolean (*_bfd_link_add_symbols) (bfd *, struct bfd_link_info *);
+
+ /* Indicate that we are only retrieving symbol values from this section. */
+ void (*_bfd_link_just_syms) (asection *, struct bfd_link_info *);
+
+ /* Copy the symbol type of a linker hash table entry. */
+#define bfd_copy_link_hash_symbol_type(b, t, f) \
+ BFD_SEND (b, _bfd_copy_link_hash_symbol_type, (b, t, f))
+ void (*_bfd_copy_link_hash_symbol_type)
+ (bfd *, struct bfd_link_hash_entry *, struct bfd_link_hash_entry *);
+
+ /* Do a link based on the link_order structures attached to each
+ section of the BFD. */
+ bfd_boolean (*_bfd_final_link) (bfd *, struct bfd_link_info *);
+
+ /* Should this section be split up into smaller pieces during linking. */
+ bfd_boolean (*_bfd_link_split_section) (bfd *, struct bfd_section *);
+
+ /* Remove sections that are not referenced from the output. */
+ bfd_boolean (*_bfd_gc_sections) (bfd *, struct bfd_link_info *);
+
+ /* Attempt to merge SEC_MERGE sections. */
+ bfd_boolean (*_bfd_merge_sections) (bfd *, struct bfd_link_info *);
+
+ /* Is this section a member of a group? */
+ bfd_boolean (*_bfd_is_group_section) (bfd *, const struct bfd_section *);
+
+ /* Discard members of a group. */
+ bfd_boolean (*_bfd_discard_group) (bfd *, struct bfd_section *);
+
+ /* Check if SEC has been already linked during a reloceatable or
+ final link. */
+ void (*_section_already_linked) (bfd *, struct bfd_section *,
+ struct bfd_link_info *);
+
+ /* Define a common symbol. */
+ bfd_boolean (*_bfd_define_common_symbol) (bfd *, struct bfd_link_info *,
+ struct bfd_link_hash_entry *);
+
+ /* Routines to handle dynamic symbols and relocs. */
+#define BFD_JUMP_TABLE_DYNAMIC(NAME) \
+ NAME##_get_dynamic_symtab_upper_bound, \
+ NAME##_canonicalize_dynamic_symtab, \
+ NAME##_get_synthetic_symtab, \
+ NAME##_get_dynamic_reloc_upper_bound, \
+ NAME##_canonicalize_dynamic_reloc
+
+ /* Get the amount of memory required to hold the dynamic symbols. */
+ long (*_bfd_get_dynamic_symtab_upper_bound) (bfd *);
+ /* Read in the dynamic symbols. */
+ long (*_bfd_canonicalize_dynamic_symtab)
+ (bfd *, struct bfd_symbol **);
+ /* Create synthetized symbols. */
+ long (*_bfd_get_synthetic_symtab)
+ (bfd *, long, struct bfd_symbol **, long, struct bfd_symbol **,
+ struct bfd_symbol **);
+ /* Get the amount of memory required to hold the dynamic relocs. */
+ long (*_bfd_get_dynamic_reloc_upper_bound) (bfd *);
+ /* Read in the dynamic relocs. */
+ long (*_bfd_canonicalize_dynamic_reloc)
+ (bfd *, arelent **, struct bfd_symbol **);
+
+@end example
+A pointer to an alternative bfd_target in case the current one is not
+satisfactory. This can happen when the target cpu supports both big
+and little endian code, and target chosen by the linker has the wrong
+endianness. The function open_output() in ld/ldlang.c uses this field
+to find an alternative output format that is suitable.
+@example
+ /* Opposite endian version of this target. */
+ const struct bfd_target * alternative_target;
+
+ /* Data for use by back-end routines, which isn't
+ generic enough to belong in this structure. */
+ const void *backend_data;
+
+@} bfd_target;
+
+@end example
+
+@findex bfd_set_default_target
+@subsubsection @code{bfd_set_default_target}
+@strong{Synopsis}
+@example
+bfd_boolean bfd_set_default_target (const char *name);
+@end example
+@strong{Description}@*
+Set the default target vector to use when recognizing a BFD.
+This takes the name of the target, which may be a BFD target
+name or a configuration triplet.
+
+@findex bfd_find_target
+@subsubsection @code{bfd_find_target}
+@strong{Synopsis}
+@example
+const bfd_target *bfd_find_target (const char *target_name, bfd *abfd);
+@end example
+@strong{Description}@*
+Return a pointer to the transfer vector for the object target
+named @var{target_name}. If @var{target_name} is @code{NULL},
+choose the one in the environment variable @code{GNUTARGET}; if
+that is null or not defined, then choose the first entry in the
+target list. Passing in the string "default" or setting the
+environment variable to "default" will cause the first entry in
+the target list to be returned, and "target_defaulted" will be
+set in the BFD if @var{abfd} isn't @code{NULL}. This causes
+@code{bfd_check_format} to loop over all the targets to find the
+one that matches the file being read.
+
+@findex bfd_get_target_info
+@subsubsection @code{bfd_get_target_info}
+@strong{Synopsis}
+@example
+const bfd_target *bfd_get_target_info (const char *target_name,
+ bfd *abfd,
+ bfd_boolean *is_bigendian,
+ int *underscoring,
+ const char **def_target_arch);
+@end example
+@strong{Description}@*
+Return a pointer to the transfer vector for the object target
+named @var{target_name}. If @var{target_name} is @code{NULL},
+choose the one in the environment variable @code{GNUTARGET}; if
+that is null or not defined, then choose the first entry in the
+target list. Passing in the string "default" or setting the
+environment variable to "default" will cause the first entry in
+the target list to be returned, and "target_defaulted" will be
+set in the BFD if @var{abfd} isn't @code{NULL}. This causes
+@code{bfd_check_format} to loop over all the targets to find the
+one that matches the file being read.
+If @var{is_bigendian} is not @code{NULL}, then set this value to target's
+endian mode. True for big-endian, FALSE for little-endian or for
+invalid target.
+If @var{underscoring} is not @code{NULL}, then set this value to target's
+underscoring mode. Zero for none-underscoring, -1 for invalid target,
+else the value of target vector's symbol underscoring.
+If @var{def_target_arch} is not @code{NULL}, then set it to the architecture
+string specified by the target_name.
+
+@findex bfd_target_list
+@subsubsection @code{bfd_target_list}
+@strong{Synopsis}
+@example
+const char ** bfd_target_list (void);
+@end example
+@strong{Description}@*
+Return a freshly malloced NULL-terminated
+vector of the names of all the valid BFD targets. Do not
+modify the names.
+
+@findex bfd_seach_for_target
+@subsubsection @code{bfd_seach_for_target}
+@strong{Synopsis}
+@example
+const bfd_target *bfd_search_for_target
+ (int (*search_func) (const bfd_target *, void *),
+ void *);
+@end example
+@strong{Description}@*
+Return a pointer to the first transfer vector in the list of
+transfer vectors maintained by BFD that produces a non-zero
+result when passed to the function @var{search_func}. The
+parameter @var{data} is passed, unexamined, to the search
+function.
+