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Diffstat (limited to 'misc-utils/lsblk.8.adoc')
| -rw-r--r-- | misc-utils/lsblk.8.adoc | 58 |
1 files changed, 54 insertions, 4 deletions
diff --git a/misc-utils/lsblk.8.adoc b/misc-utils/lsblk.8.adoc index d4b13f2..577ff71 100644 --- a/misc-utils/lsblk.8.adoc +++ b/misc-utils/lsblk.8.adoc @@ -20,9 +20,11 @@ lsblk - list block devices By default, the command prints all block devices (except RAM disks) in a tree-like format. The same device can be repeated in the tree if it relates to other devices. The *--merge* option is recommended for more complicated setups to gather groups of devices and describe complex N:M relationships. +The tree-like output (or *children[]* array in the JSON output) is enabled only if NAME column it present in the output or when *--tree* command line option is used. See also *--nodeps* and *--list* to control the tree formatting. + The default output, as well as the default output from options like *--fs* and *--topology*, is subject to change. So whenever possible, you should avoid using default outputs in your scripts. Always explicitly define expected columns by using *--output* _columns-list_ and *--list* in environments where a stable output is required. -Use *lsblk --help* to get a list of all available columns. +Use *lsblk --list-columns* to get a list of all available columns. Note that *lsblk* might be executed in time when *udev* does not have all information about recently added or modified devices yet. In this case it is recommended to use *udevadm settle* before *lsblk* to synchronize with udev. @@ -39,6 +41,9 @@ Disable all built-in filters and list all empty devices and RAM disk devices too *-b*, *--bytes*:: include::man-common/in-bytes.adoc[] +*-H*, *--list-columns*:: +List the available columns, use with *--json* or *--raw* to get output in machine-readable format. + *-D*, *--discard*:: Print information about the discarding capabilities (TRIM, UNMAP) for each device. @@ -63,7 +68,7 @@ Include devices specified by the comma-separated _list_ of major device numbers. Use ASCII characters for tree formatting. *-J*, *--json*:: -Use JSON output format. It's strongly recommended to use *--output* and also *--tree* if necessary. +Use JSON output format. It's strongly recommended to use *--output* and also *--tree* if necessary. Note that *children[]* is used only if NAME column or *--tree* is used. *-l*, *--list*:: Produce output in the form of a list. The output does not provide information about relationships between devices and since version 2.34 every device is printed only once if *--pairs* or *--raw* not specified (the parsable outputs are maintained in backwardly compatible way). @@ -84,7 +89,7 @@ Output info about virtio devices only. Do not print a header line. *-o*, *--output* _list_:: -Specify which output columns to print. Use *--help* to get a list of all supported columns. The columns may affect tree-like output. The default is to use tree for the column 'NAME' (see also *--tree*). +Specify which output columns to print. Use *--list-columns* to get a list of all supported columns. The columns may affect tree-like output. The default is to use tree for the column 'NAME' (see also *--tree*). + The default list of columns may be extended if _list_ is specified in the format _+list_ (e.g., *lsblk -o +UUID*). @@ -97,6 +102,50 @@ Produce output in the form of key="value" pairs. The output lines are still orde *-p*, *--paths*:: Print full device paths. +*-Q*, *--filter* _expr_:: +Print only the devices that meet the conditions specified by the expr. The +filter is assessed prior to lsblk collecting data for all output columns. Only +the necessary data for the lazy evaluation of the expression is retrieved from +the system. This approach can enhance performance when compared to +post-filtering, as commonly done by tools such as grep(1). ++ +This feature is EXPERIMENTAL. See also *scols-filter*(5). For example +exclude sda and sdb, but print everything else ('!~' is a negative regular +expression matching operator): +____ + lsblk --filter 'NAME !~ "sd[ab]"' +____ + +*--highlight* _expr_:: +Colorize lines matching the expression. +This feature is EXPERIMENTAL. See also *scols-filter*(5). + +*--ct* _name_ [: _param_ [: _function_ ]]:: +Define a custom counter. The counters are printed after the standard output. +The _name_ is the custom name of the counter, the optional _param_ is the name of the column +to be used for the counter, and the optional _function_ specifies +the aggregation function, supported functions are: count, min, max, or sum. The +default is count. ++ +If the _param_ is not specified, then the counter counts the number of lines. This +feature is EXPERIMENTAL. See also *--ct-filter*. ++ +For example, *--ct MyCounter:SIZE:sum* will count the summary for SIZE from all lines; +and to count the number of SATA disks, it is possible to use: +____ + + lsblk --ct-filter 'TYPE=="disk" && TRAN=="sata"' --ct "Number of SATA devices" +____ + + +*--ct-filter* _expr_:: +Define a restriction for the next counter. This feature is EXPERIMENTAL. See also *--ct* +and *scols-filter*(5). For example, aggregate sizes by device type: +____ + lsblk --ct-filter 'TYPE=="part"' --ct Partitions:SIZE:sum \ + --ct-filter 'TYPE=="disk"' --ct WholeDisks:SIZE:sum +____ + *-r*, *--raw*:: Produce output in raw format. The output lines are still ordered by dependencies. All potentially unsafe characters are hex-escaped (\x<code>) in the NAME, KNAME, LABEL, PARTLABEL and MOUNTPOINT columns. @@ -175,9 +224,10 @@ mailto:kzak@redhat.com[Karel Zak] == SEE ALSO -*ls*(1), *blkid*(8), *findmnt*(8) +*ls*(1), +*scols-filter*(5) include::man-common/bugreports.adoc[] |