xlibtrace displays the interaction between X11
client programs and the X11 client shared library
(libX11.so) by showing the Xlib calls that are
made. Output is shown in a style similar to
strace(1). It works by using the $LD_PRELOAD
dynamic linker option to insert itself between the
target X11 client program and libX11.so. This
allows it to "intercept" all calls to X functions,
whereupon it has the opportunity to print the name
of the function being called, along with any
arguments and return value. This can be
particularly useful when analyzing the behavior of
closed-source X11 programs.
