Unset (Bash)
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Use unset to delete a variable, a function or a reference. man unset
doesn't return anything, but there is help:
$ help unset unset: unset [-f] [-v] [-n] [name ...] Unset values and attributes of shell variables and functions. For each NAME, remove the corresponding variable or function. Options: -f treat each NAME as a shell function -v treat each NAME as a shell variable -n treat each NAME as a name reference and unset the variable itself rather than the variable it references Without options, unset first tries to unset a variable, and if that fails, tries to unset a function. Some variables cannot be unset; also see `readonly'. Exit Status: Returns success unless an invalid option is given or a NAME is read-only.
You can unset multiple entities at once:
unset site site_bal site_bal_cb site_bal_non_cb site_non_bal
It's fascinating: https://wiki.bash-hackers.org/commands/builtin/unset
No man page or --help
Why there is no man page or --help
flag [1]:
There is not man unset because it is a built-in command and for the built-in commands there is instead help. For some built-in command it exists an external executable too. In case of doubt try e.g. type mycommnad. For example type unset and it will answer you unset is a shell builtin. If you want to know if it exists the executable too try which echo (another built-in) and it will say where it is. The --option_long is typical of the executable command. Try echo --help and /bin/echo --help. :-)