int zip_set_file_extra(struct zip *archive, zip_uint64_t index); "const char *extra" "int len"
DESCRIPTIONThe zip_set_file_extra function sets the extra field for the file at position index in the zip archive to extra of length len. If extra is NULL and len is 0, the file extra field will be removed.
RETURN VALUESUpon successful completion 0 is returned. Otherwise, -1 is returned and the error information in archive is set to indicate the error.
ERRORSzip_set_file_extra fails if:
- index is not a valid file index in archive, or len is less than 0 or longer than the maximum extra field length in a zip file (65535).
- Required memory could not be allocated.