Chapter 16. Consoles in Wine

16.1. Consoles

Written by John Richardson Maintained by Joseph Pranevich

(Extracted from wine/documentation/console)

16.1.1. Console - First Pass

Consoles are just xterms created with the -Sxxn switch. A pty is opened and the master goes to the xterm side and the slave is held by the wine side. The console itself is turned into a few HANDLE32s and is set to the STD_*_HANDLES.

It is possible to use the WriteFile and ReadFile commands to write to a win32 console. To accomplish this, all K32OBJs that support I/O have a read and write function pointer. So, WriteFile calls K32OBJ_WriteFile which calls the K32OBJ's write function pointer, which then finally calls write.

[this paragraph is now out of date] If the command line console is to be inherited or a process inherits its parent's console (-- can that happen???), the console is created at process init time via PROCESS_InheritConsole. The 0, 1, and 2 file descriptors are duped to be the STD_*_HANDLES in this case. Also in this case a flag is set to indicate that the console comes from the parent process or command line.

If a process doesn't have a console at all, its pdb->console is set to NULL. This helps indicate when it is possible to create a new console (via AllocConsole).

When FreeConsole is called, all handles that the process has open to the console are closed. Like most K32OBJs, if the console's refcount reaches zero, its K32OBJ destroy function is called. The destroy kills the xterm if one was open.

Also like most k32 objects, we assume that (K32OBJ) header is the first field so the casting (from K32OBJ*to CONSOLE*) works correctly.

FreeConsole is called on process exit (in ExitProcess) if pdb->console is not NULL.

16.1.4. DOS (Generic) Console Support