Scripting Facilities for x3270 and s3270
SYNOPSIS
x3270 -script [x3270-options]
s3270 [s3270-options]
Script(command[,arg...])
DESCRIPTION
The x3270 scripting facilities allow x3270 and s3270
to be operated under the control of another program.
There are two basic methods. The first is the peer script facility,
invoked by the
x3270 -script switch (s3270 functions exclusively
in script mode). This runs x3270 or s3270 as a child of another
process. Typically this would be a script using expect(1) or the
co-process facility of the Korn Shell ksh(1). When the -script
switch is given, x3270 looks for commands on its standard input,
and places the responses on standard output and standard error output.
The second method is the child script facility, invoked by the
Script()
action. This runs a script as a child process of x3270 or s3270.
The child has access to pipes connected to x3270 or s3270;
x3270 or s3270 look for commands on one pipe, and places
the responses on the other. (The file descriptor of the pipe for commands
to x3270 or s3270 is passed in the environment variable X3270INPUT;
the file descriptor of the pipe for responses from x3270 or s3270
is passed in the environment variable X3270OUTPUT.)
(It is possible to mix the two methods: A script can invoke another
script with the Script() action. Scripts may also be implicitly
nested when a script invokes the
Connect() action, and the ibm_hosts
file specifies a login script for that host name.)
Commands are X actions; the syntax is the same as for the right-hand
side of an X translation table (an x3270 keymap), with two exceptions:
only one action may appear per line, and if no parameters are needed by
the action, the parentheses may be omitted.
Any x3270 or s3270 action may be specified. Several new
actions have been defined for use by scripts, and the behavior of certain
other actions (and of x3270 in general) is different when an action
is initiated by a script.
Some actions generate output; some may delay completion until the certain
external events occur, such as the host unlocking the keyboard. The completion
of every command is marked by a two-line message. The first line is the
current status of x3270 or s3270, documented below. If the
command is successful, the second line is the string "ok"; otherwise it
is the string "error".
STATUS FORMAT
The status message consists of 11 blank-separated fields:
-
1 Keyboard State
-
If the keyboard is unlocked, the letter U. If the keyboard is locked
waiting for a response from the host, or if not connected to a host, the
letter L. If the keyboard is locked because of an operator error
(field overflow, protected field, etc.), the letter E.
-
2 Screen Formatting
-
If the screen is formatted, the letter F. If unformatted or in ANSI
mode, the letter U.
-
3 Field Protection
-
If the field containing the cursor is protected, the letter P. If
unprotected or unformatted, the letter U.
-
4 Connection State
-
If connected to a host, the string C(hostname). Otherwise,
the letter N.
-
5 Emulator Mode
-
If connected in 3270 mode, the letter I. If connected in ANSI line
mode, the letter L. If connected in ANSI character mode, the letter
C. If not connected, the letter N.
-
6 Model Number (2-5)
-
7 Number of Rows
-
The current number of rows defined on the screen. The host can request
that x3270 or s3270 use a 24x80 screen, so this number may
be smaller than the maximum number of rows possible with the current model.
-
8 Number of Columns
-
The current number of columns defined on the screen, subject to the same
difference for rows, above.
-
9 Cursor Row
-
The current cursor row (zero-origin).
-
10 Cursor Column
-
The current cursor column (zero-origin).
-
11 Window ID
-
The X window identifier for the main
x3270 window, in hexadecimal
preceded by
0x. For s3270, this is zero.
DIFFERENCES
When an action is initiated by a script, x3270 behaves in several
different ways:
If an error occurs, the usual pop-up window does not appear. Instead,
the text is written to standard error output.
If end-of-file is detected on standard input, x3270 exits. (A
script can exit without killing x3270 by using the CloseScript()
action, below.) Note that this applies to peer scripts only; end-of-file
on the pipe connected to a child script simply causes the pipes to be closed
and the Script() action to complete.
The Quit() action always causes x3270 to exit. (When called
from the keyboard, it will exit only if not connected to a host.)
The Clear(), Enter(), PF(), and PA() actions
will not complete until the host unlocks the keyboard. If the parameter
to a String() action includes a code for one these actions, it will
also wait for the keyboard to unlock before completing. Similarly, the
Script() action does not complete until end-of-file is detected
on the pipe or the CloseScript() action is called by the child process.
NEW ACTIONS
The following actions have been defined or modified for use with scripts.
(Note that unlike the status line display, the row and col
coordinates used in these actions use [0,0] as their origin, not [1,1]).
-
AnsiText()
-
Outputs whatever data that has been output by the host in ANSI mode since
the last time that AnsiText() was called. The data is preceded by
the string data:, and has had all control characters expanded
into C backslash sequences.
This is a convenient way to capture ANSI mode output in a synchronous
manner without trying to decode the screen contents.
-
Ascii(row, col, rows, cols)
Ascii(row, col, len)
Ascii(len)
Ascii()
-
Outputs an ASCII text representation of the screen contents. Each line
is preceded by the string data:, and there are no control characters.
If all four parameters are given, a rectangular region of the screen
is output.
If three parameters are given, len characters are output, starting
at the specified row and column.
If only the len parameter is given, that many characters are
output, starting at the cursor position.
If no parameters are given, the entire screen is output.
-
AsciiField()
-
Outputs an ASCII text representation of the field containing the cursor.
The text is preceded by the string data:.
-
Connect(hostname)
-
Connects to a host. The action does not return until
x3270 or s3270
is successfully connected in the proper mode, or the connection fails.
-
CloseScript(status)
-
Causes x3270 to stop reading commands from the script. This is useful
to allow a peer script to exit, with
x3270 proceeding interactively.
(Without this action, x3270 would exit when it detected end-of-file
on standard input.) If the script was invoked by the Script() action,
the optional
status is used as the return status of Script();
if nonzero,
Script() will complete with an error, and if this script
was invoked as part of login through the ibm_hosts file, the connection
will be broken.
-
ContinueScript(param)
-
Allows a script that is waiting in a PauseScript() action, below,
to continue. The param given is output by the PauseScript()
action.
-
Disconnect()
-
Disconnects from the host.
-
Ebcdic(row, col, rows, cols)
Ebcdic(row, col, len)
Ebcdic(len)
Ebcdic()
-
The same function as Ascii() above, except that rather than generating
ASCII text, each character is output as a hexadecimal EBCDIC code, preceded
by
0x.
-
EbcdicField()
-
The same function as AsciiField() above, except that it generates
hexadecimal EBCDIC codes.
-
Expect(text)
Expect(text, timeout)
-
Pauses the script until the specified text appears in the data stream
from the host, or the specified timeout (in seconds) expires. If
no timeout is specified, the default is 30 seconds.
Text
can contain standard C-language escape (backslash) sequences. No wild-card
characters or pattern anchor characters are understood.
Expect()
is valid only in ANSI mode.
-
Info(message)
-
Pops up an informational message.
-
MoveCursor(row, col)
-
Moves the cursor to the specified coordinates.
-
PauseScript()
-
Stops a script until the ContinueScript() action, above, is executed.
This allows a script to wait for user input and continue. Outputs the single
parameter to ContinueScript().
-
Snap()
-
Saves a copy of the screen image and status in a temporary buffer.
This copy can be queried with other Snap()
actions to allow a script to examine a consistent screen image, even when the
host may be changing the image (or even the screen dimensions)
dynamically.
-
Snap(Ascii,...)
-
Performs the Ascii() action on the saved screen image.
-
Snap(Cols)
- Returns the number of columns in the saved screen image.
-
Snap(Ebcdic,...)
- Performs the Ebcdic() action on the saved screen image.
-
Snap(Rows)
- Returns the number of rows in the saved screen image.
-
Snap(Status)
- Returns the status line from when the screen was last saved.
-
Transfer(keyword=value,...)
-
Invokes IND$FILE file transfer. Note that this action requires that the
IND$FILE program be installed on the IBM host, and that the 3270 cursor
be located in a field that will accept a TSO or VM/CMS command.
-
-
Because of the complexity and number of options for file transfer, the
parameters to the Transfer action take the unique form of option=value,
and can appear in any order. The options are:
Option Required? Default Other Values
------------------------------------------------------------------
Direction No send receive
HostFile Yes
LocalFile Yes
Host No tso vm
Mode No ascii binary
Cr No remove add, keep
Exist No keep replace, append
Recfm No fixed, variable, undefined
Lrecl No
Blksize No
Allocation No tracks, cylinders, avblock
PrimarySpace No
SecondarySpace No
-
The option details are as follows.
-
Direction
-
send (the default) to send a file to the host, receive to
receive a file from the host.
-
HostFile
-
The name of the file on the host.
-
LocalFile
-
The name of the file on the local workstation.
-
Host
-
The type of host (which dictates the form of the IND$FILE command): tso
(the default) or vm.
-
Mode
-
Use ascii (the default) for a text file, which will be translated
between EBCDIC and ASCII as necessary. Use binary for non-text files.
-
Cr
-
Controls how Newline characters are handled when transferring Mode=ascii
files. remove (the default) strips Newline characters in local files
before transferring them to the host. add adds Newline characters
to each host file record before transferring it to the local workstation.
keep preserves Newline characters when transferring a local file
to the host.
-
Exist
-
Controls what happens when the destination file already exists. keep
(the default) preserves the file, causing the Transfer action to
fail. replace overwrites the destination file with the source file.
append appends the source file to the destination file.
-
Recfm
-
Controls the record format of files created on the host. fixed creates
a file with fixed-length records. variable creates a file with variable-length
records. undefined creates a file with undefined-length records
(TSO hosts only). The Lrecl option controls the record length or
maximum record length for Recfm=fixed and Recfm=variable
files, respectively.
-
Lrecl
-
Specifies the record length (or maximum record length) for files created
on the host.
-
Blksize
-
Specifies the block size for files created on the host. (TSO hosts only.)
-
Allocation
-
Specifies the units for the TSO host PrimarySpace and SecondarySpace
options: tracks, cylinders or avblock.
-
PrimarySpace
-
Primary allocation for a file created on a TSO host. The units are given
by the Allocation option.
-
SecondarySpace
-
Secondary allocation for a file created on a TSO host. The units are given
by the Allocation option.
-
Wait(3270Mode)
-
Used when communicating with a host that switches between ANSI mode and
3270 mode. Pauses the script or macro until the host negotiates 3270 mode,
then waits for a formatted screen as above.
For backwards compatitibility, Wait(3270) is equivalent to
Wait(3270Mode).
-
Wait(Disconnect)
-
Pauses the script until the host disconnects.
-
Wait(InputField)
-
A useful utility for use at the beginning of scripts and after the
Connect()
action. In 3270 mode, waits until the screen is formatted, and the host
has positioned the cursor on a modifiable field. In ANSI mode, waits until
the host sends at least one byte of data.
For backwards compatitibility, Wait() is equivalent to
Wait(InputField).
-
Wait(NVTmode)
-
Used when communicating with a host that switches between 3270 mode and
ANSI mode. Pauses the script or macro until the host negotiates ANSI mode,
then waits for a byte from the host as above.
For backwards compatitibility, Wait(ansi) is equivalent to
Wait(NVTMode).
-
Wait(Output)
-
Pases the script until the host sends further output.
Used when the host unlocks the keyboard (allowing the script to proceed after
an Enter, PF or PA action), but has not finished updating
the screen.
This action is usually invoked in a loop that uses the Ascii or
Ebcdic action to scan the screen for some pattern that indicates that
the host has fully processed the last command.
SEE ALSO
expect(1)
ksh(1)
x3270(1)
s3270(1)
Last modified 26. August 2000