Directives 

MNEMONIC

Define File Command Sequence

Format

MNEMONIC [(chan)]mnm_name$=esc_sequ$

Where:

chan

Channel or logical file number for which the mnemonic is defined.

mnm_name$

Valid mnemonic name, enclosed in apostrophes. String expression.

esc_sequ$

Escape or command sequence required by the file/device in order to process the mnemonic. String expression.

Description

Use the MNEMONIC directive to define additional mnemonics for files and/or devices. Once you define a mnemonic for a given logical file number, it stays active until the channel is closed. When PxPlus encounters a user-defined mnemonic in a PRINT or INPUT statement, it converts the mnemonic to the character string in the escape sequence.

Under WindX

WindX supports the use of this MNEMONIC directive via the [WDX] tag. After opening a channel across a WindX connection, all declared mnemonics (except '*R' and '*X') are sent automatically to the WindX workstation. PxPlus considers the '*R' and '*X' mnemonics to be local to the server unless you use the [WDX] tag in declaring them. ('*R' declares an operating system command to execute on channel close, and '*X' declares a program to call on channel close.)

Example:

This is an example of the EXECUTE command under WindX (prior to v4.20):

if WDX%<>$00$
     then execute "[WDX]mnemonic(lfo)'5X'=$1B+hex$"
     else goto MY_LABEL

Defining Special Processing When a File is Closed

Three special mnemonics come into play when a file is closed, and these may all be defined using the MNEMONIC directive:

 

*X

Contains the name of a program, with optional entry point, to call prior closure. This program can use LFA to find the handle of the file being closed.

 

*C

Contains a string of data that will be output to the file prior closure. This will not be sent to a Windows printer ( *WINPRT*) unless opened in raw mode ( *WINDEV*).

 

*R

Contains an operating system command line to INVOKE after the file is fully closed. Generally, this would be used to send the file to the OS spooling system or elsewhere, such as email.

When a file is closed, the system will look for the existence of these mnemonics and, if defined, will process them in the order defined above.

See Also

[WDX] Direct Action to Client Machine
Mnemonics

Examples

Example:

To define and use a mnemonic:

open (1)"/dev/printerxx"
mnemonic 'US'=esc+"_" ! Define mnemonic

print (1)'US',"Title line...", ! Underscored

Example:

The example below illustrates how the MNEMONIC directive can be used for flexible text fonts on a screen in Windows.

Define the font and the logical screen size in a statement. To assign settings for the PxPlus standard mnemonics 'CP' and 'SP':

mnemonic (0)'CP'="Courier New,-8":120,40
mnemonic (0)'SP'="*":80,25

A subsequent PRINT 'CP' directive will change the screen font to Courier New with a size of 8 points, and PRINT 'SP' will restore the screen font to standard print.

Note:
The TEXT plane font must always be a fixed font.

WindX Examples:

open (chan)"[WDX]\\mach\printer_share"
mnemonic (chan)'FF'=$0C$ ! automatically goes to WindX workstation
mnemonic (chan)'*R'="erase "+filename$ ! local to server, not workstation
mnemonic (chan)'*R'="[WDX]erase "+filename$ ! on workstation, not server