+ /* File descriptor for sockets and serial port connections, and for
+ reading output from async subprocesses; otherwise -1. */
+ int fd;
+ /* PID for subprocess, either async or not; otherwise -1. */
+ int pid;
+ /* Handle to an event object that is signaled when a read operation
+ is completed, either successfully (in which case there're indeed
+ "characters available") or not. Used by sys_select to wait for
+ output from subprocesses or socket/serial connections. */
+ HANDLE char_avail;
+ /* Handle to an event that is signaled to wake up the reader thread
+ and tell it to try reading more output from a subprocess. */
+ HANDLE char_consumed;
+ /* Handle to the reader thread to read output from a subprocess or a
+ socket or a comm port. */
+ HANDLE thrd;
+ /* Handle to the console window of a subprocess. Used to forcibly
+ terminate it by sys_kill. */
+ HWND hwnd;
+ /* Information about subprocess returned by CreateProcess. Includes
+ handles to the subprocess and its primary thread, and the
+ corresponding process ID and thread ID numbers. The PID is
+ mirrored by the 'pid' member above. The process handle is used
+ to wait on it. */
+ PROCESS_INFORMATION procinfo;
+ /* Status of subprocess/connection and of reading its output. For
+ values, see the enumeration above. */
+ volatile int status;
+ /* Holds a single character read by _sys_read_ahead, when a
+ subprocess has some output ready. */
+ char chr;
+ /* Used for async read operations on serial comm ports. */
+ OVERLAPPED ovl_read;
+ /* Used for async write operations on serial comm ports. */
+ OVERLAPPED ovl_write;
+ /* Input file, if any, for this subprocess. Should only be non-NULL
+ for async subprocesses. */
+ char *input_file;
+ /* If non-zero, the subprocess input file is temporary and should be
+ deleted when the subprocess exits. */
+ int pending_deletion;