@section File formatsA format is a BFD concept of high level file contents type. Theformats supported by BFD are:@itemize @bullet@item@code{bfd_object}@end itemizeThe BFD may contain data, symbols, relocations and debug info.@itemize @bullet@item@code{bfd_archive}@end itemizeThe BFD contains other BFDs and an optional index.@itemize @bullet@item@code{bfd_core}@end itemizeThe BFD contains the result of an executable core dump.@findex bfd_check_format@subsubsection @code{bfd_check_format}@strong{Synopsis}@examplebfd_boolean bfd_check_format (bfd *abfd, bfd_format format);@end example@strong{Description}@*Verify if the file attached to the BFD @var{abfd} is compatiblewith the format @var{format} (i.e., one of @code{bfd_object},@code{bfd_archive} or @code{bfd_core}).If the BFD has been set to a specific target before thecall, only the named target and format combination ischecked. If the target has not been set, or has been set to@code{default}, then all the known target backends isinterrogated to determine a match.  If the default targetmatches, it is used.  If not, exactly one target must recognizethe file, or an error results.The function returns @code{TRUE} on success, otherwise @code{FALSE}with one of the following error codes:@itemize @bullet@item@code{bfd_error_invalid_operation} -if @code{format} is not one of @code{bfd_object}, @code{bfd_archive} or@code{bfd_core}.@item@code{bfd_error_system_call} -if an error occured during a read - even some file mismatchescan cause bfd_error_system_calls.@item@code{file_not_recognised} -none of the backends recognised the file format.@item@code{bfd_error_file_ambiguously_recognized} -more than one backend recognised the file format.@end itemize@findex bfd_check_format_matches@subsubsection @code{bfd_check_format_matches}@strong{Synopsis}@examplebfd_boolean bfd_check_format_matches (bfd *abfd, bfd_format format,    char ***matching);@end example@strong{Description}@*Like @code{bfd_check_format}, except when it returns FALSE with@code{bfd_errno} set to @code{bfd_error_file_ambiguously_recognized}.  In thatcase, if @var{matching} is not NULL, it will be filled in witha NULL-terminated list of the names of the formats that matched,allocated with @code{malloc}.Then the user may choose a format and try again.When done with the list that @var{matching} points to, the callershould free it.@findex bfd_set_format@subsubsection @code{bfd_set_format}@strong{Synopsis}@examplebfd_boolean bfd_set_format (bfd *abfd, bfd_format format);@end example@strong{Description}@*This function sets the file format of the BFD @var{abfd} to theformat @var{format}. If the target set in the BFD does notsupport the format requested, the format is invalid, or the BFDis not open for writing, then an error occurs.@findex bfd_format_string@subsubsection @code{bfd_format_string}@strong{Synopsis}@exampleconst char *bfd_format_string (bfd_format format);@end example@strong{Description}@*Return a pointer to a const string@code{invalid}, @code{object}, @code{archive}, @code{core}, or @code{unknown},depending upon the value of @var{format}.