noble (7) tickit_debug.7.gz

NAME

       Tickit_Debug - debug logging support for libtickit

SYNOPSIS

       $ TICKIT_DEBUG_FLAGS=W TICKIT_DEBUG_FILE=tickit.log a-tickit-program

DESCRIPTION

       The  libtickit  library  contains a debug logging system that other parts of the library use to report on
       interesting events and behaviours, that may help developers to observe internal details and assist in the
       development and debugging of applications that use the library.

       Debug  messages  themselves  each  have  a  flag  name,  which  is a short string identifying the library
       component or event that caused that message. A given set of these flags can be enabled during a debugging
       session,  causing  only  those  messages to be printed. Messages pertaining to flags that are not enabled
       will not be printed.

FLAGS

       Each flag name starts with an upper-case letter indicating the library  component  it  relates  to,  then
       lower-case letters to indicate the particular kind of event or message within that component.

   B
       These messages relate to TickitRenderBuffer (tickit_renderbuffer(7)).

       Bd     Drawing operations such as tickit_renderbuffer_text(3).

       Bf     Flushing

       Bs     Stack state save and restore.

       Bt

   I
       These messages relate to input-system events.

       Ik     Keyboard keypresses.

       Im     Mouse movement and button or wheel events.

       Ir     Terminal resize.  Transformations (translation, clipping and masking).

   W
       These messages relate to windows.

       W*     Window destroyed.

       Wd     Damage to root window.

       Wx     Window is exposed.

       Wh     Window hierarchy changed.

       Ws     Window scrolls.

       Wsr    Window propagates a scrollrect to its underlying terminal.

ENVIRONMENT

       The  debugging  support  is controlled by the following environment variables, which should be set before
       the application starts, or early during its initialisation before it has invoked any libtickit functions.

       TICKIT_DEBUG_FLAGS
              A comma-separated list of the flags or flag categories to enable for printing.  Entire  categories
              of  flags can be enabled by list just the initial capital letter of its name. All the flags can be
              enabled at once by setting the name *.

       TICKIT_DEBUG_FILE
              Gives the name of a file to open in append mode to write logging lines to.

       TICKIT_DEBUG_FD
              Gives a file descriptor number to write logging lines to.

       One technique that may be useful to observe logging in real-time while the application runs is to arrange
       for  the  application  to run in a new terminal but have it log debugging output to an existing one. This
       may be achieved using

       $ TICKIT_DEBUG_FD=3 TICKIT_DEBUG_FLAGS=... $TERM my-tickit-app 3>&2

       This requests that libtickit log to file descriptor 3, which has been created by dup(2)ing  the  original
       shell's  standard  output.  Debug  logging  will therefore be printed to the existing terminal where this
       command was executed, while the application itself draws its output to the newly-created one.

FUNCTIONS

       The  debug  system  is  initialised  by  calling  tickit_debug_init(3).  Messages  can  be  logged  using
       tickit_debug_logf(3) and tickit_debug_vlogf(3).

SEE ALSO

       tickit(7), tickit_term(7), tickit_renderbuffer(7), tickit_window(7)

                                                                                                 TICKIT_DEBUG(7)