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HP OpenVMS DCL Dictionary
HELP
The HELP command invokes the Help facility to display information about
use of the system, including formats and explanations of commands,
parameters, qualifiers, and system messages. In response to the Topic?
prompt, you can:
- Type the name of the command or topic for which you need help.
- Type INSTRUCTIONS for more detailed instructions on how to use HELP.
- Type HINTS if you are not sure of the name of the command or topic
for which you need help.
- Type /MESSAGE for help with the HELP/MESSAGE utility.
- Type a question mark (?) to redisplay the most recently requested
text.
- Press RETURN one or more times to exit from HELP.
You can abbreviate any topic name, although ambiguous abbreviations
result in all matches being displayed.
Format
HELP [topic[subtopic...]]
Parameter
topic[subtopic...]
Specifies the topics or topic and subtopics on which you want
information from a help library.
Description
Information within help libraries is arranged in a hierarchical manner.
The levels are as follows:
- None---If you do not specify a keyword, the Help facility describes
the HELP command and lists the topics that are documented in the root
library. Each item in the list is a keyword in the first level of the
hierarchy.
- Topic-name---If you specify a keyword by naming a topic, the Help
facility describes the topic as it is documented in either the root
library or in one of the other enabled default libraries. Keywords for
additional information available on this topic are listed.
- Topic-name subtopic---If you specify a subtopic following a topic,
the Help facility provides a description of the specified subtopic.
- @filespec followed by any of the previous levels---If you specify a
help library to replace the current root library, the Help facility
searches that library for a description of the topic or subtopic
specified. The file specification must take the same form as the file
specification included with the /LIBRARY command qualifier. However, if
the specified library is an enabled user-defined default library, the
file specification can be abbreviated to any unique leading substring
of that default library's logical name translation.
To use the Help facility on OpenVMS in its simplest form, enter the
HELP command from your terminal. The Help facility displays a list of
topics at your terminal and the prompt Topic?. To see information on
one of the topics, type the topic name after the prompt. The system
displays information on that topic.
If the topic has subtopics, the HELP command lists the subtopics and
displays the Subtopic? prompt. To get information on one of the
subtopics, type the name after the prompt. To see information on
another topic, press Return. You can now ask for information on another
topic when the Help facility displays the Topic? prompt. Press Return
to exit the Help facility and return to DCL command level.
If you use an asterisk (*) in place of any keyword, the HELP command
displays all information available at the level that the asterisk
replaces. For example, HELP COPY * displays all the subtopics under the
topic COPY.
If you use an ellipsis (...) immediately after any primary keyword, the
Help facility displays all the information on the specified topic and
all subtopics of that topic. For example, HELP COPY... displays
information on the COPY topic as well as information on all the
subtopics under COPY. The ellipsis can only be used from the topic
level; it cannot be used from the subtopic level.
The asterisk (*) and the percent sign (%) wildcard characters are
allowed in the keyword.
Qualifiers
/EXACT
Use with the /PAGE=SAVE and /SEARCH qualifiers to specify a search
string that must match the search string exactly and must be enclosed
with quotation marks (" ").
If you specify the /EXACT qualifier without the /SEARCH qualifier,
exact search mode is enabled when you set the search string with the
Find (E1) key.
/HIGHLIGHT[=keyword]
Use with the /PAGE=SAVE and /SEARCH qualifiers to specify the type of
highlighting you want when a search string is found. When a string is
found, the entire line is highlighted. You can use the following
keywords: BOLD, BLINK, REVERSE, and UNDERLINE. BOLD is the default
highlighting.
/INSTRUCTIONS (default)
/NOINSTRUCTIONS
Displays an explanation of the HELP command along with the list of
topics (if no topic is specified). By default, the HELP command display
includes a description of the facility and the format, along with the
list of topics. If you specify the /NOINSTRUCTIONS qualifier, only the
list of topics is displayed.
/LIBLIST (default)
/NOLIBLIST
Displays any auxiliary help libraries.
/LIBRARY=filespec
/NOLIBRARY
Uses an alternate help library instead of the default system library,
SYS$HELP:HELPLIB.HLB. The specified library is used as the main (root)
help library, and is searched for Help facility information before any
user-defined default help libraries are checked.
If you omit the device and directory specification, the default is
SYS$HELP, the logical name of the location of the system help
libraries. The default file type is .HLB.
The /NOLIBRARY qualifier excludes the default help library from the
library search order.
/MESSAGE
Displays descriptions of system messages. See the HELP/MESSAGE command
in this manual.
/OUTPUT[=filespec]
/NOOUTPUT
Controls where the output of the command is sent. By default, the
output is sent to SYS$OUTPUT, the current process default output stream
or device.
If you enter the /OUTPUT qualifier with a partial file specification
(for example, /OUTPUT=[JONES]), HELP is the default file name and .LIS
is the default file type. The asterisk (*) and the percent sign (%)
wildcard characters are not allowed.
If you enter the /NOOUTPUT qualifier, output is suppressed.
/PAGE[=keyword]
/NOPAGE (default)
Controls the display of information on the screen.
You can use the following keywords with the /PAGE qualifier:
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CLEAR_SCREEN
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Clears the screen before each page is displayed.
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SCROLL
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Displays information one line at a time.
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SAVE[=
n]
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Enables screen navigation of information, where
n is the number of pages to store.
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The /PAGE=SAVE qualifier allows you to navigate through screens of
information. The /PAGE=SAVE qualifier stores up to 5 screens of up to
255 columns of information. When you use the /PAGE=SAVE qualifier, you
can use the following keys to navigate through the information:
| Key Sequence |
Description |
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Up arrow key, Ctrl/B
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Scroll up one line.
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Down arrow key
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Scroll down one line.
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Left arrow key
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Scroll left one column.
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Right arrow key
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Scroll right one column.
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Find (E1)
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Specify a string to find when the information is displayed.
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Insert Here (E2)
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Scroll right one half screen.
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Remove (E3)
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Scroll left one half screen.
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Select (E4)
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Toggle 80/132 column mode.
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Prev Screen (E5)
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Get the previous page of information.
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Next Screen (E6), Return, Enter, Space
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Get the next page of information.
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F10, Ctrl/Z
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Exit. (Some utilities define these differently.)
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Help (F15)
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Display utility help text.
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Do (F16)
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Toggle the display to oldest/newest page.
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Ctrl/W
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Refresh the display.
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The /PAGE qualifier is not compatible with the /OUTPUT qualifier.
/PROMPT (default)
/NOPROMPT
Permits you to solicit further information interactively. If you
specify the /NOPROMPT qualifier, the Help facility returns you to DCL
command level after it displays the requested information.
If the /PROMPT qualifier is in effect, one of four different prompts is
displayed, requesting you to specify a particular help topic or
subtopic. Each prompt represents a different level in the hierarchy of
help information. The four prompt levels are as follows:
- Topic?---The root library is the main library and you are not
currently examining the Help facility information for a particular
topic.
- [library-spec] Topic?---The root library is a library other than
the main library and you are not currently examining the Help facility
information for a particular topic.
- [keyword] Subtopic?---The root library is the main library and you
are currently examining the Help facility information for a particular
topic (or subtopic).
- A combination of 2 and 3.
When you encounter one of these prompts, you can enter any one of the
responses described in the following table:
| Response |
Current Prompt Environment |
Action |
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keyword[...]
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1,2
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Searches all enabled libraries for the keyword.
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|
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3,4
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Searches additional help libraries for the current topic (or subtopic)
for the keyword.
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@filespec
keyword[...]
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1,2
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Same as above, except that the library specified by @filespec is now
the root library. If the specified library does not exist, the Help
facility treats @filespec as a normal keyword.
Displays a list of topics available in the root library.
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|
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3,4
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Same as above; treats @filespec as a normal keyword.
Displays the list of subtopics of the current topic (or subtopics)
for which help exists.
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[Return]
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1
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Exits from the Help facility.
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2
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Changes root library to main library.
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3,4
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Prompts for a topic or subtopic at the next higher level.
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[Ctrl/Z]
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1,2,3,4
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Exits from the Help facility.
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/SEARCH="string"
Use with the /PAGE=SAVE qualifier to specify a string that you want to
find in the information being displayed. Quotation marks are required
for the /SEARCH qualifier, if you include spaces in the text string.
You can also dynamically change the search string by pressing the Find
key (E1) while the information is being displayed. Quotation marks are
not required for a dynamic search.
/USERLIBRARY=(level[,...])
/NOUSERLIBRARY
Names the levels of search for information in auxiliary libraries. The
levels are as follows:
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PROCESS
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Libraries defined at process level
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GROUP
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Libraries defined at group level
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SYSTEM
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Libraries defined at system level
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ALL
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All libraries (default)
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NONE
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No libraries (same as the /NOUSERLIBRARY qualifier)
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Auxiliary help libraries are libraries defined with the logical names
HLP$LIBRARY, HLP$LIBRARY_1, HLP$LIBRARY_2, and so on. Libraries are
searched for information in this order: root (current) library, main
library (if not current), libraries defined at process level, libraries
defined at group level, libraries defined at system level, and the root
library. If the search fails, the root library is searched a second
time so that the context is returned to the root library from which the
search was initiated. The default is the /USERLIBRARY=ALL qualifier. If
you specify only one level for the Help facility to search, you can
omit the parentheses.
/WRAP
/NOWRAP (default)
Use with the /PAGE=SAVE qualifier to limit the number of columns to the
width of the screen and to wrap lines that extend beyond the width of
the screen to the next line.
The /NOWRAP qualifier extends lines beyond the width of the screen and
can be seen when you use the scrolling (left and right) features
provided by the /PAGE=SAVE qualifier.
Examples
| #1 |
$ HELP
HELP
.
. (HELP message text and list of topics)
.
Topic?
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In this example, the HELP command is entered without any qualifiers or
parameters. This example produces a display of the help topics
available from the root help library, SYS$HELP:HELPLIB.HLB.
If you enter one of the listed topics in response to the Topic? prompt,
the Help facility displays information about that topic and a list of
subtopics (if there are any). If one or more subtopics exist, the Help
facility prompts you for a subtopic, as follows:
Topic? ASSIGN
ASSIGN
.
. (HELP message text and subtopics)
.
ASSIGN Subtopic?
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If you type a subtopic name, the Help facility displays information
about that subtopic, as follows:
ASSIGN Subtopic? Name
ASSIGN
Name
.
. (HELP message text and subtopics, if any)
.
ASSIGN Subtopic?
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If one or more sub-subtopics exist, the Help facility prompts you for a
sub-subtopic; otherwise, as in the previous example, the facility
prompts you for another subtopic of the topic you are currently
inspecting.
Entering a question mark (?) redisplays the Help facility message and
options at your current level. Pressing Return does either of the
following:
- Moves you back to the previous help level if you are in a subtopic
level.
- Terminates the Help facility if you are at the first level.
Pressing Ctrl/Z terminates the Help facility at any level.
The HELP command in this example displays a description of the COPY
command and of the command's parameters and qualifiers. Note that the
ellipsis can be used only from the topic level; it cannot be used from
the subtopic level.
| #3 |
$ HELP/NOPROMPT ASSIGN/GROUP
.
. (ASSIGN/GROUP HELP message)
.
$
$ HELP/NOPROMPT/PAGE EDIT *
.
. (HELP messages on all first-level EDIT subtopics)
.
$
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The two HELP commands request help on specific topics. In each case,
the HELP command displays the help message you request and then returns
you to DCL command level and the dollar sign prompt ($).
The first command requests help on the /GROUP qualifier of the ASSIGN
command. The asterisk (*) in the second example is a wildcard
character. It signals the Help facility to display information about
all EDIT subtopics, which are then displayed in alphabetical order. The
/NOPROMPT qualifier suppresses prompting in both sample commands. The
/PAGE qualifier on the second HELP command causes output to the screen
to stop after each screen of information is displayed.
| #4 |
$ HELP FILL
Sorry, no documentation on FILL
Additional information available:
.
. (list of first-level topics )
.
Topic? @EDTHELP FILL
FILL
.
. (FILL HELP message)
.
@EDTHELP Topic?
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When you enter a request for help on a topic that is not in the default
help library, you can instruct the Help facility to search another help
library for the topic. In this example, entering the command @EDTHELP
FILL instructs the Help facility to search the help library
SYS$HELP:EDTHELP.HLB for information on FILL, an EDT editor command.
The Help facility displays the message and prompts you for another EDT
editor topic.
| #5 |
$ SET DEFAULT SYS$HELP
$ DEFINE HLP$LIBRARY EDTHELP
$ DEFINE HLP$LIBRARY_1 MAILHELP
$ DEFINE HLP$LIBRARY_2 BASIC
$ DEFINE HLP$LIBRARY_3 DISK2:[MALCOLM]FLIP
$ HELP REM
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You can use logical names to define libraries for the Help facility to
search automatically if it does not find the specified topic in the
OpenVMS root help library. This sequence of commands instructs the Help
facility to search libraries in addition to the default root library,
SYS$HELP:HELPLIB.HLB.
The four DEFINE statements create logical names for the four
user-defined help libraries that the Help facility is to search after
it has searched the root library. The first three entries are help
libraries in the current default directory. By default, the Help
facility searches for user-defined help libraries in the directory
defined by the logical name SYS$HELP. The fourth entry is the help
library FLIP.HLB in the directory DISK2:[MALCOLM]. Note that the
logical names that you use to define these help libraries must be
numbered consecutively; that is, you cannot skip any numbers.
The Help facility first searches the root library for REM. It then
searches the libraries HLP$LIBRARY, HLP$LIBRARY_1, HLP$LIBRARY_2, and
so on, until it finds REM or exhausts the libraries it knows it can
search. When it finds REM in the BASIC.HLB library, the Help facility
displays the appropriate help information and prompts you for a
subtopic in that library. If you request information on a topic not in
the BASIC.HLB library, the Help facility once again searches the help
libraries you have defined.
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