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When using the X11 library (which may be implied, e.g., when linking the GTK
library) in combination with Bobcat, make sure the X11 library is passed to
the linker before the bobcat library is specified.
E.g., use -lX11 -lbobcat
If the bobcat library is specified before the X11 library the following
stand-in functions defined in the bobcat library will be used:
`XOpenDisplay'
`XCloseDisplay'
`XFlush'
`XWarpPointer'
`XQueryPointer'
`XGetWindowAttributes'
These symbols were included in the bobcat library to prevent `undefined
reference' linker errors from being generated when shared libraries are used
but the X11 library is *not* used.
What happens when X11 is specified before bobcat is that although the bobcat
library defines stand-in functions they are presented to the linker only after
the linker has seen the similarly named symbols in the X11 library. The linker
uses the symbols first encountered, and will therefore properly use the
symbols defined in the X11 library.
However, if the X11 library is not used (e.g., Xpointer is not used) and if
bobcat itself would not define the above symbols then those symbols would not
be defined in the shared libraries inspected by the linker, producing linker
errors.
Although these errors could be prevented by specifying the option
-Wl,--allow-shlib-undefined
requiring this option seems like a more complex instruction than requiring
that when using the X11 library it must be specified before the bobcat
library.
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