If an executable file contains a reference to a function defined in
one of its associated shared objects, the symbol table section for
that file shall contain an entry for that symbol. The
st_shndx member of that
This signals to the dynamic linker that the symbol definition for that
function is not contained in the executable file itself. If that symbol
has been allocated a procedure linkage table entry in the executable file,
st_value member for
that symbol table entry is non-zero, the value shall contain the virtual
address of the first instruction of that procedure linkage table entry.
contains zero. This procedure linkage table entry address is used by
the dynamic linker in resolving references to the address of the function.