x3270if provides an interface between scripts and
the 3270 emulators x3270, c3270, and s3270.
x3270if performs one of three functions.
In action mode (the default), it passes a single action and optional
parameters to the emulator for execution;
the result of the command is written to standard output.
In status mode, it reports to standard output the value of one of
the emulator's status fields.
In iterative mode, it forms a continuous conduit between a script and
the emulator.
OPTIONS
-v
Turns on verbose debug messages, showing the literal data that is passed
between the emulator and x3270if.
-sfield
Puts x3270if in status mode: it outputs the value of an emulator
status field.
Field is an integer in the range 0 through 11.
The value 0 is a no-op and is used only to return exit status indicating the
state of the emulator.
The indices 1-11 and meanings of each field are documented on the
x3270-script(1) manual page.
-i
Puts x3270if in iterative mode.
Data from x3270if's standard input is copied to the
emulator's script input; data from the
emulator's script output is copied to
x3270if's standard output.
x3270if
runs until it detects end-of-file on its standard input or on the
output from the emulator.
(This mode exists primarily to give expect(1)
a process to run, on systems which do not support bidirectional pipes.)
EXIT STATUS
In action mode, if the requested action succeeds,
x3270if exits with status 0.
If the action fails, x3270if exits with status 1.
In iterative mode, x3270if
exits with status 0 when it encounters end-of-file.
If there is an operational error within x3270if
itself, such as a command-line syntax error, missing environment
variable, or an unexpectedly closed pipe,
x3270if exits with status 2.
ENVIRONMENT
x3270, c3270, and s3270
use a pair of pipes for communication with each child process.
The values of the file descriptors for these pipes are encoded as text
in two environment variables, which are required by
x3270if:
X3270OUTPUT
Output from the emulator, input to the child process.
X3270INPUT
Input to the emulator, output from the child process.
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation.
