39. Subprocesses

The fields of a process are:

name

A string, the name of the process.

command

A list containing the command arguments that were used to start this process.

filter

A function used to accept output from the process instead of a buffer, or nil.

sentinel

A function called whenever the process receives a signal, or nil.

buffer

The associated buffer of the process.

pid

An integer, the Unix process ID.

childp

A flag, non-nil if this is really a child process. It is nil for a network connection.

mark

A marker indicating the position of the end of the last output from this process inserted into the buffer. This is often but not always the end of the buffer.

kill_without_query

If this is non-nil, killing XEmacs while this process is still running does not ask for confirmation about killing the process.

raw_status_low

raw_status_high

These two fields record 16 bits each of the process status returned by the wait system call.

status

The process status, as process-status should return it.

tick

update_tick

If these two fields are not equal, a change in the status of the process needs to be reported, either by running the sentinel or by inserting a message in the process buffer.

pty_flag

Non-nil if communication with the subprocess uses a PTY; nil if it uses a pipe.

infd

The file descriptor for input from the process.

outfd

The file descriptor for output to the process.

subtty

The file descriptor for the terminal that the subprocess is using. (On some systems, there is no need to record this, so the value is -1.)

tty_name

The name of the terminal that the subprocess is using, or nil if it is using pipes.

39.0.1 Ben's separate stderr notes (probably obsolete)

This node contains some notes that Ben kept on his separate subprocess workspace. These notes probably describe changes and features that have already been included in XEmacs 21.5; somebody should check and/or ask Ben.

ben-separate-stderr-improved-error-trapping

this is an old workspace, very close to being done, containing

• subprocess stderr output can be read separately; needed to fully implement call-process with asynch. subprocesses.

• huge improvements to the internal error-trapping routines (i.e. the routines that call Lisp code and trap errors); Lisp code can now be called from within redisplay.

• cleanup and simplification of C-g handling; some things work now that never used to.

• see the ChangeLogs in the workspace.