Here's the same example written in 68000 assembler. The principles are the same as with : you must always open a library before using any of its functions. However, in assembler, library bases are treated a little differently than in C. In C, you assign the library base you get from OpenLibrary() to a global variable and forget about it (the system handles the rest). In assembler, the library base must always be in register A6 whenever calling any of the functions in the library. You get the library base for any library except Exec, by calling OpenLibrary(). For Exec, you get the library base from the longword in memory location 4 ($0000 0004). Exec is opened automatically by the system at boot time, and its library base is stored there. easy.asm The Amiga library functions are set up to accept parameters in certain 68000 registers and always return results in data register D0. This allows programs and functions written in assembler to communicate quickly. It also eliminates the dependence on the stack frame conventions of any particular language. Amiga library functions use registers D0, D1, A0 and A1 for work space and use register A6 to hold the library base. Do not expect these registers to be the same after calling a function. All routines return a full 32 bit longword unless noted otherwise.
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