How can I get a help message for zsh builtins?

Question

If I want to get a brief usage message for a bash builtin, I can use help <builtin> at a command prompt, e.g.

$ help export
export: export [-fn] [name[=value] ...] or export -p
    Set export attribute for shell variables.

    Marks each NAME for automatic export to the environment of subsequently
    executed commands.  If VALUE is supplied, assign VALUE before exporting.

    Options:
      -f        refer to shell functions
      -n        remove the export property from each NAME
      -p        display a list of all exported variables and functions

    An argument of `--' disables further option processing.

    Exit Status:
    Returns success unless an invalid option is given or NAME is invalid.

How can I do this in zsh? I've tried

% export --help
zsh: bad option: -e

and

% help export
zsh: command not found: help

Also the word "help" isn't anywhere in man zshbuiltins.

the_velour_fog · Answer 1 · 2016-05-12T00:38:57.980

8

thanks to @don_crissti linking through this Arch wiki documentation.
For some reason the code on the Arch wiki causes this error on invocation

/home/velour/.zshrc:unalias:368: no such hash table element: run-help

_{zsh --version => zsh 5.1.1 (x86_64-ubuntu-linux-gnu)}

so to get it to work, I added the below block to ~/.zshrc, then commented out the alias commands.

autoload -Uz run-help
autoload -Uz run-help-git
autoload -Uz run-help-svn
autoload -Uz run-help-svk
#unalias run-help
#alias help=run-help

and simply invoke with

run-help <builtin>

So now I get

% run-help export

export [ name[=value] ... ]
       The specified names are marked for automatic export to the envi-
       ronment  of subsequently executed commands.  Equivalent to type-
       set -gx.  If a parameter specified does not already exist, it is
       created in the global scope.

edited May 12 '16 at 00:38

answered May 12 '16 at 00:20

the_velour_fog

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@don_crissti I have updated my answer with details of error and zsh version. – the_velour_fog May 12 '16 at 00:40
Maybe it's [this](https://bugs.launchpad.net/ubuntu/+source/zsh/+bug/305346) – don_crissti May 12 '16 at 00:48
13

I tried this without uncommenting out the aliases, and I just get the zshbuiltins manual page. How can I get help for a specific builtin without searching for it in there? – addison May 30 '16 at 20:55

score 0 · Answer 2 · answered Aug 01 '21 at 08:32

0

An alternative to the run-help function above is the zman mentioned in a Reddit comment. It’s part of Zinit, but seems to work independently.

answered Aug 01 '21 at 08:32

Franklin Yu

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score 0 · Answer 3 · answered Oct 15 '22 at 08:05

Adding the following to .zshrc worked for me.
(building upon the answer of the_velour_fog)

unalias run-help
alias help=run-help
autoload -Uz run-help

Before run-help was an alias for man.

$ zsh --version
zsh 5.9 (x86_64-apple-darwin18.7.0)
$ zsh
\$ type run-help
run-help is an alias for man
\$ unalias run-help
\$ type run-help
run-help not found
\$ autoload -Uz run-help
\$ type run-help
run-help is an autoload shell function
\$ alias help=run-help
\$ help export
export [ name[=value] ... ]
       The specified names are marked for automatic export to the envi-
       ronment  of subsequently executed commands.  Equivalent to type-
       set -gx.  If a parameter specified does not already exist, it is
       created in the global scope.

score -1 · Answer 4 · answered Jun 30 '23 at 09:32

-1

They have an own man page:

man zshbuiltins

answered Jun 30 '23 at 09:32

Mecki

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And the question says, "*the word "help" isn't anywhere in `man zshbuiltins`*." So this answer adds no value. – Toby Speight Jul 02 '23 at 09:04
All the information that `help` would ever provide is found on the man page of `zshbuiltins`. If you want to know the options of `export`, you use `help export` in bash but in zsh you use `man zshbuiltins` and there you get the options for `export`. After all you also use `man ls` and not `help ls`; zsh just treats built-ins like non-builtins as the POSIX standard does not require anything to be built-in. And `export` is found on the man page, help not as zsh simply doesn't know any command named help and POSIX does not require that to exist at all. – Mecki Jul 02 '23 at 16:59

How can I get a help message for zsh builtins?

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