4 Using Shortcuts #
The commands listed in the previous sections always used all the required
options. However, cset does have a shortcut facility
that will execute certain commands without specifying all options. An
effort has been made to do this with the “principle of least
surprise”. This means that if you do not specify options, but do
specify parameters, then the outcome of the command should be intuitive as
possible.
Using shortcuts is not necessary. In fact, you can use either shortcuts or
long options. However, using long options instead of shortcuts does have a
use case: when you write a script intended to be self-documenting, or
perhaps when you generate cset documentation.
To begin, the subcommands shield,
set and proc can themselves be
shortened to the fewest number of characters that are unambiguous. For
example, the following commands are identical:
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Long method |
Short method |
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The proc command can be shortened to
p, while shield and
set need two letters to disambiguate.
4.1 shield Subcommand Shortcuts #
The shield subcommand supports two areas with
shortcuts: the short method (when there are no options given and where to
shield is the common use case), and the long method (which makes
-p/--pid optional for the -s/--shield
and -u/--unshield options).
For the common use case of actually shielding either a PIDSPEC or execing
a command into the shield, the following cset commands
are equivalent.
Long method | Short method |
|---|---|
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When using the -s or -u shield/unshield
options, it is optional to use the -p option to specify
a PIDSPEC. For example:
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Long method |
Short method |
|---|---|
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4.2 set Subcommand Shortcuts #
The set subcommand has a limited number of shortcuts.
The option --set is optional usually
and the --list option is also optional to
list sets. For example, these commands are equivalent:
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Long method |
Short method |
|---|---|
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In fact, if you want to apply either the list or the destroy options to
multiple cpusets with one cset command, you will not
need to use the -s option. For example:
csetse -d myset yourset ourset --> destroys cpusets: myset, yourset and oursetcsetse -l prio_high prio_med prio_low --> lists only cpusets prio_high, prio_med and prio_low --> the -l is optional in this case since list is default
4.3 proc Subcommand Shortcuts #
For the proc subcommand, the -s, -t and
-f options to specify the cpuset, the origination cpuset
and the destination cpuset can sometimes be optional. For example, the
following commands are equivalent. To list tasks in cpusets:
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Long method |
Short method |
|---|---|
or
or
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To execute a process into a cpuset:
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Long method |
Short method |
|---|---|
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Moving tasks into and out of cpusets have the following shortcuts.
To move a PIDSPEC into a cpuset:
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Long method |
Short method |
|---|---|
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To move all tasks from one cpuset to another:
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Long method |
Short method |
|---|---|
or
or
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