Count extra fields for file in zip
libzip (-lzip)
#include <zip.h>
zip_int16_t
zip_file_extra_fields_count(struct zip *archive, zip_uint64_t index, zip_flags_t flags);
zip_int16_t
zip_file_extra_fields_count_by_id(struct zip *archive, zip_uint64_t index, zip_uint16_t extra_field_id, zip_flags_t flags);
The zip_file_extra_fields_count() function counts the extra fields for the file at position index in the zip archive.
The following flags are supported:
ZIP_FL_CENTRAL
Count extra fields from the archive's central directory.
ZIP_FL_LOCAL
Count extra fields from the local file headers.
ZIP_FL_UNCHANGED
Count the original unchanged extra fields, ignoring any changes made.
The zip_file_extra_fields_count_by_id() function counts the extra fields with ID (two-byte signature) extra_field_id. The other arguments are the same as for zip_file_extra_fields_count().
Extra fields that are the same in the central directory and the local file header are merged into one. Therefore, the counts with ZIP_FL_CENTRAL and ZIP_FL_LOCAL do not need to add up to the same value as when given ZIP_FL_CENTRAL|ZIP_FL_LOCAL at the same time.
Upon successful completion, the requested number of extra fields is returned. Otherwise, -1 is returned and the error code in archive is set to indicate the error.
zip_file_extra_fields_count() and zip_file_extra_fields_count_by_id() fail if:
[ZIP_ER_NOENT]
index is not a valid file index in archive.
Dieter Baron <[email protected]> and Thomas Klausner <[email protected]>