/* strerror.x * char *strerror(int errnum) * * Returns a pointer to an appropriate error message string. */ .define _strerror .data .extern _sys_nerr, _sys_errlist unknown: .asciz 'Unknown error' .text _strerror: mov bx,sp mov bx,2(bx) mov ax,#unknown /* default return is "Unknown error" */ or bx,bx jle exit cmp bx,_sys_nerr jge exit sal bx,#1 mov ax,_sys_errlist(bx) exit: ret