Adding upstream version 4.9.0.upstream/4.9.0upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 39 insertions, 0 deletions

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+WIP notes on hacking the Screen source.
+
+* Screen commands are handled by the DoAction function in process.c.
+  The local variable nr is set to an integer value representing the
+  command to be evaluated; for every command `foo', there is an
+  integer value RC_FOO for use as nr's value to represent it. Find
+  the matching case label to follow processing of the command.
+   
+  The RC_FOO values are defined in comm.h, which is automatically
+  generated by comm.sh, based on the names of the commands
+  themselves (found in comm.c).
+
+* The current display is held in the global variable "display".
+  Variable names like D_foo are shorthands for display->d_foo (where d_foo
+  is a member of "struct display").
+
+* Names like D_IS, D_TI, D_SG usually refer to the values of various
+  termcap features of the current display. These are found in term.h,
+  which is automatically generated from term.c by term.sh.
+
+* The main input-reading function for handling user input from a display,
+  is disp_readev_fn in display.c. This also handles automatic transformation
+  of mouse-tracking codes from display coordinates to screen-window
+  coordinates, and decodes characters from the display's encoding, passing
+  it on to the foreground input processor.
+
+  Input is passed through ProcessInput in process.c to handle
+  keybindings (specified by bindkey and such), and then processed by
+  layer-specific input-processing functions, which you'll find in
+  instances of struct LayFuncs. For instance, keystrokes are processed
+  by:
+
+        normal windows:         WinPrGocess
+        window in copy-mode:    MarkProcess
+        window list:            WListProcess
+        command input line:     InpProcess
+
+* Handling string escapes (in hardstatus and the like), such as %w or
+  %{= bw}, is done in screen.c, MakeWinMsgEv().