1) Only one tag with a particular name can be attached to a device
at a time. This significantly simplifies the library, and was needed
to allow the cache file to be re-read and changes integrated into the
in-core version of the data structure in a simpler fashion than earlier
versions of the library.
2) To accomodate this, the ext2/ext3 filesystems are now always tagged
as "ext2" type filesystems. Ext3 filesystems are tagged with a
SEC_TYPE tag with the value ext3.
3) The new blkid_read_cache() function checks the mod time of the
cache file, and if the file has been changed since the last time the
cache file was read into memory, it is re-read. This function is now
called before probing all of the devices in the system or searching
all devices in the cache for a specific tag value.
4) After probing all devices, blkid_flush_cache() is called to write
out the cache file. This assures that all of the hard work involved
in doing a blkid_probe_all() is saved to disk.
read.c (parse_tag): Do not return that blkid_tag when parsing
the blkid.tag file.
resolve.c (blkid_get_token, blkid_get_tagname_devname): Fold in
code from removed functions
tag.c (blkid_create_tag): Don't return the newly tag strcture
any more, as it's not needed.
(blkid_find_tag_cache, blkid_get_tag_cache,
blkid_token_to_tag, blkid_find_tv_tags): Remove these
functions, as they are either only used once or have
interfaces that should be deprecated.
(blkid_find_tag_dev, blkid_find_head_cache): Replace use
of blkid_tag with one or two const char * type/value
arguments.
(blkid_find_dev_with_tag): Fold in code from removed functions
probe.h, probe.c: Use a more sophisticated set of byte-swapping
routines which are more compact and efficient. Drop
calculation of bid_free, since it's unnecessary. Avoid
save.c (blkid_save_cache): Set the permissions on the blkid
cache file to 644.
Theodore Ts'o