Enhanced SET command
Copyright (c) 1990 Wayne D. Mingee All rights reserved
Archive ESET21 Program ESET v2.1 Suggested donation $10.00

OVERVIEW

This program manages DOS [and 4DOS] environment variables. It will:
-Handle the master or local [secondary] environment. It does find
them all including Wyse 3.1.
-Multiple operands per line
-Set a variable to:
System date or time
Whether under a secondary command processor
A substring of a string
-Append or Prepend a string
-Arithmetically process by:
adding a +-value
shifting the value left/right n positions
And/Xor with a value
-Change a one or all occurrences of a string to another
-Take user input from Stdin with:
Issue a prompt message
limiting time to start replying and input to certain characters
limiting length of input and terminating input when input full
-Trim leading/trailing blanks from result

-Convert to upper case
-No limit on length of variables.
-Display the environment with size, used and free totals and returns
the free amount in a variable
-Works with DOS 2.0+, 4DOS and should work in a OS/2 DOS box.
Registration gets additional programs that:
-Manipulate I/O ports. Can be used to test printer status, carrier
detect, etc. rearrange bios port addresses.
-Get file information, path, size, date, etc. Do a findfirst/findnext.
-Reallocate the environment size. Release unused copies. Fix the size.
-Maintain a lifo/fifo list in a variable.
-Release the environment of TSR's that don't.
-Commit system specs, drives, etc, to variables at boot.
-Library routine for doing environment work.

QUICK START

------------------------------- NOTE -------------------------------
This program will create variables longer than 127. Care must
be used when intermixing the use of the DOS SET command, since DOS
will only process the first 127 positions and may leave an invalid
variable in the environment. Also variables can contain characters
which DOS may not handle correctly.
--------------------------------------------------------------------
If using 4DOS you must either rename ESET or disable the 4DOS
command with SETDOS /I-ESET. Also to use the prepend operation (^)
you have to change the 4DOS command separator character with SETDOS
/Cc.
--------------------------------------------------------------------

To test if ESET will find the environments on your system:
COMMAND /C ESET /DX Z=$C Z+=
the display should be:
[xxx] Z=1 xxx should be a hex number > 15
[xxx] Z=1 the 2nd assignment insures it was set

To set a variable: ESET name=value
To clear a variable: ESET name=
To display the contents of the environment: ESET
To take user input into a variable: ESET name "prompt message"
To edit a variable: ESET /E name ? 155
To get current date: ESET NOW=$D

PARAMETER DESCRIPTIONS

ESET name=value

Multiple sets of arguments can be supplied:
ESET [sws] [vbl] [sws] [vbl] . . .

All variable names are converted to upper case. Names cannot begin
with a switch character.

The switch character "/" used in these docs is actually replaced
by the switch character defined in DOS.

Switches may be given separately or in a string. ie: /C /D /CD

To set a value containing blanks or <>| enclose the ENTIRE
parameter in "". ie: ESET "NAME=Now is the time"
Setting ESET NAME="Now is the time" would include the quotes as part
of the variables value.

If no parameters other than switches are given the contents of the
named environment are displayed. There is no end of screen pause as
this is designed primarily for saving the environment to a file.

All output is to Stdout and may be redirected.

Any token may be created from one or more environment variables.
(ie: %Z% %Z%%X% %Z%--%X%) In BAT file use %%. If no closing % is found
before the end of the token, ie: %%NAME one is inserted and no error
is indicated. This can help to reduce the length of command line.
Also on very long variables use %% so that DOS does not include it as
part of the command line. The /M switch also effects where variables
are copied from. Given ESET /M Z=%Y% then Y would be copied from the
master environment.
All variables are resolved including those within "". To include
a % as part of a variable you have to use 2 %% [3 in BAT files].
Included variables are not tested for variables.

Default settings can be set in an environment variable equal to
the program name. This works even if ESET is renamed.


GENERAL SWITCHES

/U the value is converted to upper case.

/C a LF is output on STDOUT. This occurs immediately for each C
encountered. Can be used to separate user input on separate lines.
ie: ESET FNAME "Enter file name>" /C CNAME "Enter customer name" /C
ESET does not normally end any display with a CRLF thus allowing you
to control the display.

/T the requested operation is performed and then all leading and
trailing blanks are removed from the value.

/D the results are displayed on stdout as name=value with one trailing
space but no CRLF.

/X the hex value of the return code for each operation is displayed on
stdout as [xxx]. If less than 16 then it is an error code otherwise
it is the displacement of the variable into the environment.

/M the master environment is used instead of the local [secondary]
shell's. If operating under the primary shell it has no effect.
Remember when setting the master environment while under a secondary
shell that the new value will not be available to normal DOS batch
commands since the local environment was not affected. Use the /R
switch to set both.

/R after the operation is performed the resultant value is copied to
the master environment. If operating under the primary shell it has
no effect.

/B processing is terminated with ERRORLEVEL 3 if any error has
occurred up to this point.
ie: ESET PATH*=/C:\ESET;/C:\ESET;/ /B
would return ERRORLEVEL 3 if the PATH does not contain the directory
C:\ESET

/N processing is terminated with ERRORLEVEL 3 if no error has occurred
up to this point.
ie: ESET PATH*=/C:\ESET;/C:\ESET;/ /N PATH^=C:\ESET;
would prepend the directory C:\ESET to the PATH if it does not already
exists in it.

Switches UMDXTR are toggles. Each occurrence reverses the state.

If the value begins with a $ then ESET will perform certain special
functions to create the value. To set a value beginning with a $ use
two $. The $ codes are:

$D - returns current date mm-dd-yyyy
$T - returns current time hh:mm:ss
$Sn1,n2,string - returns substring of variable starting at n1 for
n2 positions. 1 = position 1.
$+ [+/-]n2 - add integer n2 to variable
$& [+/-]n2 - and integer n2 to variable
$^ [+/-]n2 - xor integer n2 to variable
$[ [+/-]n2 - shift variable left n2 bits
$] [+/-]n2 - shift variable right n2 bits
$C - returns a 0 if running under the primary command
processor and a 1 if it is a secondary.
$E - gets value of byte at 40:F0 which if you are using RELENV
[available in the registered version] is the return code of
last program termination.

If the name ends in one of the following characters the special
operation is performed with the value. To end a name in one of these
use 2. [name**]

- remove value from variable
^ prepend value to variable
+ append value to variable
* value is in two parts separated by a delimiter equal to the
first char. The first occurrence of the first part is
replaced by the second part. ie: /yy/xx/ replaces yy with
xx. Replacing a NULL string is the same as prepend.
Replacing a NULL with a NULL will return ERRORLEVEL 0 if the
VARIABLE exists and a 1 if not.
@ same as * but changes all occurrences. Replacing a NULL
string will make the variable fill up the unused space in the
environment.

ERRORLEVELS RETURNED

1 problem setting environment variable
name* - old value not found
name- - value not found
processing continues

2 problem processing the command
syntax error
could not find the environment
insufficient space in environment
processing terminated

3 /B or /N switch was satisfied, processing terminated

Function change-all [@] always returns code 0.

variable $E is set to the ERRORLEVEL with the following exceptions:
FOR USER INPUT
0-511 Ascii value of last key input. [3=Ctrl-C]
extended Ascii codes are 256-511
512 is set for timeout

when displaying the environment $E contains the amount of free space.


USER INPUT

ESET [switches] name prompt [valid-chars] [+-length] [time limit]

Name is the variable name and can include one of the special
operations from above [-+*^@], in which case the data input by the
user will be used to perform the operation.

Prompt is a string to be displayed. If it contains blanks or <>|
then it must be enclosed in "". It cannot contain a ".

Input is taken from Stdin and may be redirected.

SWITCHES

/E the current value of name is used as the default value which the
user can edit. An additional data item is required which is the
maximum length for the item. If the absolute value is not greater
than the current length then the current length is used and the length
cannot be increased. If it is positive then the cursor will be
positioned length+2 position from the beginning of the field. If it
is negative the cursor will be positioned 2 positions past the end of
the input. Currently, the total length of the prompt + the length of
the input must be less than the length of 2 screen lines.

/A when the user enters a character into the last position, input is
terminated and the code of that character is set in $E. Applies only
when /E is used.

/V An additional data item is required which specifies the valid
input characters. If a blank or <>| is allowed the list must be
enclosed in "". The blank must be given if allowed.

/Lnn the user has nn seconds to start responding. After the first
keystroke there is no time limit on completing. the first keystroke
does not have to be a valid character, when using /V, to stop the
timer. This must be last or only switch. [/EVL3 or /L5]

Switches VEA are toggles. Each occurrence reverses the state.

Ctrl-Z [eof] terminates all further input from STDIN but the command
line is still processed.
ie: ESET A ? B ? C ? if DATA.FIL only contains one line then variables B and C would be
cleared.
ie: ESET A ? if DATA.FIL contains more then one line the remainder of the file is
ignored.

The following control keys are available during keyboard input:

Right and left cursor, backspace, delete, home, end, insert

Ctrl-left and Ctrl-right move to the next word.

Ctrl-home restores the default value.

Ctrl-end clears from the cursor to the end of the input.

Ctrl-C [break] terminates all further processing of the command line.

Any other non-character key terminates input.

TECHNICAL

Because of the way the environment is manipulated an existing
variable maintains the same sequential position within the
environment. They are not moved to the end when they are changed.
This may be of some use otherwise but I mention it mainly because they
would not show on the display in the usual place.

If using variables longer than 128 characters you should be sure
and test them with your programs since some copy the environment into
their own workspace and therefore may have problems with long ones.
If you have trouble with a program locking up after using this, remove
the long variable and test it again.

Certain limitations, such as no " in a prompt string can be over
come by setting a variable and using it.
ie: ESET Y="huh?" Z %%Y would use the string "huh?" as the prompt.

One common problem is getting the DOS message, "Bad command or
file name", because the command is too long. This can be avoided by
using %% for variables.

Nested variables are available where DOS does the first
replacement and ESET does the next.
Given: Y contains the value %Z% and Z contains HI
ESET Y=%%%%Z Z=HI
Then: ESET A=%Y% in a BAT file would set A to HI.

Mailing address:

Wayne D. Mingee
314 N. Main St.
Bridgewater, Va 22812

Bug reports or suggestions may be sent to the above address or
Messaages can be left at one of the following BBS.

Mad Hacker 703-433-0824 Harrisonburg, VA
Computer Connection 202-547-2008 Alexandria, VA