1. Syntax

2. Implementations
    DOS  4DOS/4NT  cmd.exe  Windows PowerShell  GNU Bash 

3. Examples
    DOSBox  Python  GNU Octave 

4. See also

5. References

In computing, help is a command in various command line shells such as COMMAND.COM, cmd.exe, Bash, 4DOS/4NT, Windows PowerShell, Singularity shell, Python, MATLAB^[1] and GNU Octave.^[2] It provides online information about available commands and the shell environment.^[3]

The command is available in operating systems such as DOS, OS/2, Microsoft Windows, ReactOS, THEOS/OASIS,^[4] OS-9^[5] OpenVOS,^[6] MPE/iX,^[7] KolibriOS^[8] and also in the DEC RT-11,^[9] TOPS-10^[10] and TOPS-20^[11] operating systems. Furthermore it is available in the open source MS-DOS emulator DOSBox and in the EFI shell.^[12] The DEC OS/8 CCL help command prints information on specified OS/8 programs.^[13] On Unix, the command is part of the Source Code Control System and prints help information for the SCCS commands.

Syntax

Arguments:

• command This command-line argument specifies the name of the command about which information is to be displayed.

Implementations

DOS

The help command is available in MS-DOS 5.x and later versions of the software.

If no arguments are provided, the command lists the contents of DOSHELP.HLP. In MS-DOS 6.x this command exists as FASTHELP. In DR-DOS, HELP is a batch file that launches DR-DOS' internal help program, DOSBOOK.

The MS-DOS 6.xx help command uses QBasic to view a quickhelp HELP.HLP file, which contains more extensive information on the commands, with some hyperlinking etc. The MS-DOS 6.22 help system is included on Windows 9x CD-ROM versions as well.

PC DOS 7.xx help uses view.exe to open OS/2 style INF files (cmdref.inf, dosrexx.inf and doserror.inf), opening these to the appropriate pages.

The FreeDOS version was developed by Joe Cosentino.^[14]

4DOS/4NT

The 4DOS/4NT help command uses a text user interface to display the online help.

cmd.exe

Used without parameters, help lists and briefly describes every system command.

Windows NT-based versions use MS-DOS 5 style help. Versions before Windows Vista also have a Windows help file (NTCMDS.HLP or NTCMDS.INF) in a similar style to MS-DOS 6.

Windows PowerShell

In Windows PowerShell, help is a short form (implemented as a PowerShell function) for access to the Get-Help Cmdlet.

Windows PowerShell includes an extensive, console-based help system, reminiscent of man pages in Unix. The help topics include help for cmdlets, providers, and concepts in PowerShell.

GNU Bash

In Bash, the builtin command help^[15] lists all Bash builtin commands if used without arguments. Otherwise, it prints a brief summary of a command. Its syntax is:

Examples

DOSBox

Z:\\>help

If you want a list of all supported commands type help /all .

A short list of the most often used commands:

• 2 Fevrier Sofitel Hotel
• 2 FF
• 2FF
• 2FF card
• 2FF SIM
• 2FF SIM card
• 2 Field Engineer Regiment (South Africa)
• 2 Filipino Women
• 2 Fingers
• 2-Fluorenylacetamide
• 2-fma
• 2F (music)
• 2 for 1
• 2-Formylbenzoate dehydrogenase
• 2-formylbenzoate dehydrogenase
• 2-formyl pyridine
• 2-Formylpyridine
• 2-Formyl pyridine
• 2-formylpyridine
• 2 for the Price of 1 (The Price Is Right)
• 2-FPPP
• 2-framing
• 2 francs (World War II Belgian coin)
• 2. Frauen Bundesliga
• 2fresh Records