Clozure CL Documentation

8.4. External-Program Dictionary

[Function]

run-program
	    program args &key (wait t) pty sharing input
	    if-input-does-not-exist output (if-output-exists :error) (error
	    :output) (if-error-exists :error) status-hook
	    external-format

Invokes an external program as an OS subprocess of lisp.

program---A string or pathname which denotes an executable file. The PATH environment variable is used to find programs whose name doesn't contain a directory component.

args---A list of simple-strings

wait---Indicates whether or not run-program should wait for the EXTERNAL-PROCESS to complete or should return immediately.

pty---This option is accepted but currently ignored; it's intended to make it easier to run external programs that need to interact with a terminal device.

sharing---Sets a specific sharing mode (see :SHARING) for any streams created within RUN-PROGRAM when INPUT, OUTPUT or ERROR are requested to be a :STREAM.

input---Selects the input source used by the EXTERNAL-PROCESS. May be any of the following:

NIL Specifies that a null input stream (e.g., /dev/null) should be used.
T Specifies that the EXTERNAL-PROCESS should use the input source with which Clozure CL was invoked.
A string or pathname. Specifies that the EXTERNAL-PROCESS should receive its input from the named existing file.
:STREAM Creates a Lisp stream opened for character output. Any data written to this stream (accessible as the EXTERNAL-PROCESS-INPUT-STREAM of the EXTERNAL-PROCESS object) appears as input to the external process.
A stream. Specifies that the lisp stream should provide input to the EXTERNAL-PROCESS.

if-input-does-not-exist---If the input argument specifies the name of an existing file, this argument is used as the if-does-not-exist argument to OPEN when that file is opened.

output---Specifies where standard output from the external process should be sent. Analogous to input above.

if-output-exists---If output is specified as a string or pathname, this argument is used as the if-exists argument to OPEN when that file is opened.

error---Specifies where error output from the external process should be sent. In addition to the values allowed for output, the keyword :OUTPUT can be used to indicate that error output should be sent where standard output goes.

if-error-exists---Analogous to if-output-exists.

status-hook---A user-defined function of one argument (the EXTERNAL-PROCESS structure.) This function is called whenever Clozure CL detects a change in the status of the EXTERNAL-PROCESS.

external-format--- The external format (see Section 4.5.2, “External Formats”) for all of the streams (input, output, and error) used to communicate with the external process.

Runs the specified program in an external (Unix) process, returning an object of type EXTERNAL-PROCESS if successful.

[Function]

signal-external-process
	    proc signal-number