Release 3.0 Notes For The Operating System Reference Manual For The Lisa

Release 3.0 Notes for the Operating System Reference Manual for the Lisa These notes reflect changes and additions to the 3.0 release Lisa Operating System software. The notes update the following chapters: Chapter 1, Introduction; Chapter 2, The File System; Chapter 4, Memory Management; and Chapter 5, Exceptions and Events. Please look over these notes now, before placing them with the corresponding chapters in your binder for easy reference. Operating System .J.O Notes Introduction Olapter 1 Introduction Using the SYSCILL Unit If a Pascal program contains Operating System user-interface procedure calls, then the program's USES clause must specify the SYSCALL unit, contained in the SysCall.Obj file: ProgrSll ttyProg; l5ES {SU SYSCAlLJEJ} 5ysCalli Notes 1-1 Operating S}·'Stem J~O Notes The File System Dlapter 2 The File System New Hierarchical File S\IStem Each mounted disk volume now has a hierarchically arranged directory structure. The root directory of a volume is always present, and subdirectories may be created to contain collections of files that are logically related. Path Names (See Section 2.1) A particular file or directory is specified to the file system with a path n8l71e. A path name is a sequence of directory names, separated by dashes (-), ending in a file or directory name. For example, the path name -Jower-memos-conference.te,rt specifies that the root directory of the disk volume lower be searched for the directory memos,. and then memos be searched for the file conference.text. File and directory names are limited to 32 characters in length, and are truncated to 32 characters if too long. The 'Nm"king Oirectmy (See Section 2.2) A working directory is associated with each process in the system. When a process is created, its working directory is the root directory of the boot disk volume. A process may reassign its working directory through the SET_WORKING_DIR call. The GET_fNORKING_DIR call returns the path name of the working directory in a printable string. A path name submitted to the file system by a process may be specified relative to the process's working directory. This is done by omitting the initial dash from the path name. Suppose that the working directory is -Jower-docLJments-memos in the directory hierarchy shown below. The path name maiJ-netfo.1al1.te,rt specifies that the working directory be searched for the directory mlli~. and then mail be searched for the file netfo.1lliJ.text.. The path name conference.text specifies that the working directory be searched for the file conference.text.. The plus delimiter (+) may be substituted for the dash within a path name to indicate that the next directory in the path name is the parent of the preceding directory. The plus delimiter is typically used to trace a path by moving upward in the directory tree relative to the working directory. Again suppose that the working directory is -Jower-documents-memos. The path name +documents-boole-chap3 specifies th…