unhash

unhash [-adfms] name ...

unhash is a Zsh built-in that removes a named entry from one of the shell's internal hash tables. By default it operates on the command hash table, which caches the full path of recently executed commands. Options select an alternate table (aliases, functions, named directories, or suffix aliases) and the -m flag treats the remaining arguments as patterns matching multiple entries at once.The related built-ins unalias, unfunction, and unsetopt are thin wrappers that call unhash with the appropriate flag preset. Using unhash directly is mainly useful inside scripts and functions where the table being modified is determined dynamically.

-a

Remove regular or global aliases. Equivalent to unalias.

Remove suffix aliases.

Remove shell functions. Equivalent to unfunction.

Remove named directory entries created with hash -d.

Treat each name as a pattern; every matching entry in the selected table is removed. Patterns should be quoted to prevent filename expansion.

Available only in Zsh; Bash uses hash -d to remove a single entry and has no direct equivalent. Removing a name from the command hash table forces Zsh to re-search $PATH the next time the command is invoked, which is the usual reason for clearing stale entries after installing new binaries. Global aliases must be quoted when removed because they would otherwise be expanded before reaching unhash.

unhash has been part of Zsh since its early releases by Paul Falstad in 1990. It mirrors the design of the hash built-in but operates in reverse and was generalized to cover multiple internal tables as Zsh grew aliases, named directories, and suffix aliases.

hash(1), unalias(1), unset(1), zsh(1)