blkid_partlist

typedef struct blkid_struct_partlist *blkid_partlist;

list of all detected partitions and partitions tables

blkid_partition

typedef struct blkid_struct_partition *blkid_partition;

information about a partition

blkid_parttable

typedef struct blkid_struct_parttable *blkid_parttable;

information about a partition table

blkid_probe_enable_partitions ()

int                 blkid_probe_enable_partitions       (blkid_probe pr,
                                                         int enable);

Enables/disables the partitions probing for non-binary interface.

blkid_probe_set_partitions_flags ()

int                 blkid_probe_set_partitions_flags    (blkid_probe pr,
                                                         int flags);

Sets probing flags to the partitions prober. This function is optional.

blkid_probe_filter_partitions_type ()

int                 blkid_probe_filter_partitions_type  (blkid_probe pr,
                                                         int flag,
                                                         char *names[]);

BLKID_FLTR_NOTIN - probe for all items which are NOT IN names

BLKID_FLTR_ONLYIN - probe for items which are IN names

blkid_probe_invert_partitions_filter ()

int                 blkid_probe_invert_partitions_filter
                                                        (blkid_probe pr);

Inverts partitions probing filter

blkid_probe_reset_partitions_filter ()

int                 blkid_probe_reset_partitions_filter (blkid_probe pr);

Resets partitions probing filter

blkid_known_pttype ()

int                 blkid_known_pttype                  (const char *pttype);

blkid_partition_get_name ()

const char *        blkid_partition_get_name            (blkid_partition par);

blkid_partition_get_flags ()

unsigned long long  blkid_partition_get_flags           (blkid_partition par);

blkid_partition_get_partno ()

int                 blkid_partition_get_partno          (blkid_partition par);

blkid_partition_get_size ()

blkid_loff_t        blkid_partition_get_size            (blkid_partition par);

WARNING: be very careful when you work with MS-DOS extended partitions. The library always returns full size of the partition. If you want add the partition to the Linux system (BLKPG_ADD_PARTITION ioctl) you need to reduce the size of the partition to 1 or 2 blocks. The rest of the partition has to be unaccessible for mkfs or mkswap programs, we need a small space for boot loaders only.

For some unknown reason this (safe) practice is not to used for nested BSD, Solaris, ..., partition tables in Linux kernel.

blkid_partition_get_start ()

blkid_loff_t        blkid_partition_get_start           (blkid_partition par);

Be careful if you _not_ probe whole disk:

1) the offset is usully relative to begin of the disk -- but if you probe a fragment of the disk only -- then the offset could be still relative to the begin of the disk rather that relative to the fragment.

2) the offset for nested partitions could be releative to parent (e.g. Solaris) _or_ relative to the begin of the whole disk (e.g. bsd).

You don't have to care about such details if you proble whole disk. In such a case libblkid always returns the offset relative to the begin of the disk.

blkid_partition_get_table ()

blkid_parttable     blkid_partition_get_table           (blkid_partition par);

The "parttable" describes partition table. The table is usually the same for all partitions -- except nested partition tables.

For example bsd, solaris, etc. use a nested partition table within standard primary dos partition:

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-- dos partition table
0: sda1     dos primary partition
1: sda2     dos primary partition
   -- bsd partition table (with in sda2)
2:    sda5  bds partition
3:    sda6  bds partition

The library does not to use a separate partition table object for dos logical partitions (partitions within extended partition). It's possible to differentiate between logical, extended and primary partitions by

blkid_partition_is_{extended,primary,logical}().

blkid_partition_get_type ()

int                 blkid_partition_get_type            (blkid_partition par);

blkid_partition_get_type_string ()

const char *        blkid_partition_get_type_string     (blkid_partition par);

The type string is supported by a small subset of partition tables (e.g Mac and EFI GPT). Note that GPT uses type UUID and this function returns this UUID as string.

blkid_partition_get_uuid ()

const char *        blkid_partition_get_uuid            (blkid_partition par);

blkid_partition_is_extended ()

int                 blkid_partition_is_extended         (blkid_partition par);

blkid_partition_is_logical ()

int                 blkid_partition_is_logical          (blkid_partition par);

Note that this function returns TRUE for all partitions in all nested partition tables (e.g. BSD labels).

blkid_partition_is_primary ()

int                 blkid_partition_is_primary          (blkid_partition par);

Note, this function returns FALSE for DOS extended partitions and all partitions in nested partition tables.

blkid_partlist_get_partition ()

blkid_partition     blkid_partlist_get_partition        (blkid_partlist ls,
                                                         int n);

It's possible that the list of partitions is *empty*, but there is a valid partition table on the disk. This happen when on-disk details about partitions are unknown or the partition table is empty.

See also blkid_partlist_get_table().

blkid_partlist_get_partition_by_partno ()

blkid_partition     blkid_partlist_get_partition_by_partno
                                                        (blkid_partlist ls,
                                                         int n);

This does not assume any order of the input blkid_partlist. And correctly handles "out of order" partition tables. partition N is located after partition N+1 on the disk.

blkid_partlist_numof_partitions ()

int                 blkid_partlist_numof_partitions     (blkid_partlist ls);

blkid_partlist_devno_to_partition ()

blkid_partition     blkid_partlist_devno_to_partition   (blkid_partlist ls,
                                                         dev_t devno);

This function tries to get start and size for devno from sysfs and returns a partition from ls which matches with the values from sysfs.

This function is necessary when you want to make a relation between an entry in the partition table (ls) and block devices in your system.

blkid_partlist_get_table ()

blkid_parttable     blkid_partlist_get_table            (blkid_partlist ls);

blkid_parttable_get_id ()

const char *        blkid_parttable_get_id              (blkid_parttable tab);

The ID is GPT disk UUID or DOS disk ID (in hex format).

blkid_parttable_get_offset ()

blkid_loff_t        blkid_parttable_get_offset          (blkid_parttable tab);

Note the position is relative to begin of the device as defined by blkid_probe_set_device() for primary partition table, and relative to parental partition for nested patition tables.

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off_t offset;
blkid_partition parent = blkid_parttable_get_parent(tab);

offset = blkid_parttable_get_offset(tab);

if (parent)
     / * 'tab' is nested partition table * /
offset += blkid_partition_get_start(parent);

blkid_parttable_get_parent ()

blkid_partition     blkid_parttable_get_parent          (blkid_parttable tab);

blkid_parttable_get_type ()

const char *        blkid_parttable_get_type            (blkid_parttable tab);

blkid_probe_get_partitions ()

blkid_partlist      blkid_probe_get_partitions          (blkid_probe pr);

This is a binary interface for partitions. See also blkid_partlist_* functions.

This function is independent on blkid_do_[safe,full]probe() and blkid_probe_enable_partitions() calls.

WARNING: the returned object will be overwritten by the next blkid_probe_get_partitions() call for the same pr. If you want to use more blkid_partlist objects in the same time you have to create more blkid_probe handlers (see blkid_new_probe()).