Martin: Merge info from Command Procedure, tidy enumeration

2022-03-23T12:59:13Z

Merge info from Command Procedure, tidy enumeration

← Older revision		Revision as of 12:59, 23 March 2022
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	A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a [[DCL]] script. Command procedure files have the [[File extension\|extension]] of .COM.		A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a [[DCL]] script. Command procedure files by convention have the [[File extension\|extension]] of .COM.

	=Rules and conventions=		=Rules and conventions=
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	There are also certain conventions that it is recommended to follow to improve clarity and maintainability of the code:		There are also certain conventions that it is recommended to follow to improve clarity and maintainability of the code:

	1. Give your command procedure a name that indicates its purpose and use .COM as the file type.		# Give your command procedure a name that indicates its purpose and use .COM as the file type.
			# Use complete names for commands and qualifiers. This will help to ensure that your command procedure is upwardly compatible to future releases of OpenVMS.
	2. Use complete names for commands and qualifiers. This will help to ensure that your command procedure is upwardly compatible to future releases of OpenVMS.		# Start each command procedure with one or more [[Comment\|comment]] lines, at least stating the purpose of the command procedure.
			# End the command procedure with an EXIT or STOP statement.
	3. Start each command procedure with one or more [[Comment\|comment]] lines, at least stating the purpose of the command procedure.

	4. End the command procedure with an EXIT or STOP statement.

	=Example=		=Example=

Darya.zelenina: Created page with "A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a DCL scri..."

2018-12-19T06:16:59Z

Created page with "A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a DCL scri..."

New page

A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a [[DCL]] script. Command procedure files have the [[File extension|extension]] of .COM.

=Rules and conventions=
Command procedures in OpenVMS follow a set of rules; if they are broken, an error message is displayed and the command procedure may fail.

1. Every line in a command procedure that is not a data line has to begin with the dollar sign ($):
<nowiki>
$ if f$mode() .nes. "INTERACTIVE" then exit
</nowiki>
2. [[Comment|Comments]] begin with an exclamation point (!). Comment lines begin with a dollar sign AND an exclamation point ($!):
<nowiki>
$ if count .eq. 5 !Last element
$! Return to the previous level
</nowiki>
There are also certain conventions that it is recommended to follow to improve clarity and maintainability of the code:

1. Give your command procedure a name that indicates its purpose and use .COM as the file type.

2. Use complete names for commands and qualifiers. This will help to ensure that your command procedure is upwardly compatible to future releases of OpenVMS.

3. Start each command procedure with one or more [[Comment|comment]] lines, at least stating the purpose of the command procedure.

4. End the command procedure with an EXIT or STOP statement.

=Example=
<nowiki>
$! This command procedure displays a message based on the current day of the week.
$ say := write sys$output
$ day = f$cvtime(,,"WEEKDAY")
$! show sym day
$ say "Hooray, it's ''day'!"
</nowiki>

=Command procedures used by OpenVMS=
* [[AUTOGEN]]
* [[LOGIN.COM]]
* [[SYSTARTUP_VMS.COM]]
* [[SYLOGICALS.COM]]

Command procedure - Revision history

Martin: Merge info from Command Procedure, tidy enumeration

Darya.zelenina: Created page with "A '''command procedure''' is a file that holds a sequence of DCL commands to be executed by the system in sequence interactively or as a batch job - essentially a DCL scri..."