Process Internals
-----------------
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 Emacs 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
`nil'.)
`tty_name'
The name of the terminal that the subprocess is using, or `nil' if
it is using pipes.
`decode_coding_system'
Coding-system for decoding the input from this process.
`decoding_buf'
A working buffer for decoding.
`decoding_carryover'
Size of carryover in decoding.
`encode_coding_system'
Coding-system for encoding the output to this process.
`encoding_buf'
A working buffer for enecoding.
`encoding_carryover'
Size of carryover in encoding.
`inherit_coding_system_flag'
Flag to set `coding-system' of the process buffer from the coding
system used to decode process output.