Most functions return zero on success, non-zero on error. The return value indicates the general severity of the error, ranging from ARCHIVE_WARNING, which indicates a minor problem that should probably be reported to the user, to ARCHIVE_FATAL, which indicates a serious problem that will prevent any further operations on this archive. On error, the archive_errno function can be used to retrieve a numeric error code (see errno(2)). The archive_error_string returns a textual error message suitable for display.
archive_read_new and archive_write_new return pointers to an allocated and initialized struct archive object.
archive_read_data and archive_write_data return a count of the number of bytes actually read or written. A value of zero indicates the end of the data for this entry. A negative value indicates an error, in which case the archive_errno and archive_error_string functions can be used to obtain more information.
There are character set conversions within the archive_entry(3) functions that are impacted by the currently-selected locale.
tar(1), archive_entry(3), archive_read(3), archive_util(3), archive_write(3), tar(5)