| LPC Basics |
| Written by Descartes of Borg |
| first edition: 23 april 1993 |
| second edition: 25 may 1993 |
| |
| CHAPTER 1: Introduction to the Coding Environment |
| |
| 1.1 UNIX file structure |
| LPMuds use basic UNIX commands and its file structure. If you know |
| UNIX commands already, then note (with a few exceptions) options are |
| not available to the commands. Like DOS, UNIX is heirarchical. The |
| root directory of which all directories are sub-directories is called |
| root(/). And from those sub-directories you may have further |
| sub-directories. A directory may be referred to in two different ways: |
| 1) by its full name, or absolute name, or 2) by its relative name. |
| Absolute name refers to the directory's full path starting from / winding |
| down the directory tree until you name the directory in question. For |
| example: |
| |
| /players/descartes/obj/monster |
| |
| refers to the directory monster which is a sub-directory of obj which |
| is a sub-directory of descartes which is a sub-directory of players |
| which is a sudirectory of /. |
| |
| The relative name refers to the name relative to another directory. |
| The above example is called monster relative to /players/descartes/obj, |
| but it is also called obj/monster relative to /players/descartes, |
| descartes/obj/monster relative to /players, and finally |
| players/descartes/obj/monster relative to /. You can tell the |
| difference between absolute names and relative names because absolute |
| names always start with /. In order to know exactly which directory |
| is being named by a relative name, you naturally must know what |
| directory it is relative to. |
| |
| A directory contains sub-directories and files. LPMuds only use text files |
| inside the mudlib. Like directories, files have both absolute and |
| relative names. The most basic relative name is often referred to as the file |
| name, with the rest of the absolute name being referred to as the path. So, |
| for the file: /players/descartes/castle.c, castle.c is the file name, and |
| /players/descartes is the path. |
| |
| On some muds, a file with a file name beginning with a . (like .plan) is |
| not visible when you list files with the regular file listing command. |
| |
| 1.2 UNIX Commands |
| Along with the UNIX file structure, LPMuds use many UNIX commands. Typical |
| UNIX commands on most muds are: |
| pwd, cd, ls, rm, mv, cp, mkdir, rmdir, more, head, cat, ed |
| If you have never before seen UNIX commands, you probably are thinking this |
| is all nonsense. Well, it is, but you got to use them. Before getting |
| into what they mean though, first a discussion of current directory. |
| If you know DOS, then you know what a current working directory is. |
| At any given point, you are considered to be "in" some directory. This |
| means that any relative file or directory names you give in UNIX commands |
| are relative to that directory. For example, if my current directory is |
| /players/descartes and I type "ed castle.c" (ed is the command to edit), |
| then it assumes I mean the file /players/descartes/castle.c |
| |
| pwd: shows you your current working directory |
| cd: changes your current working directory. You may give either relative |
| or absolute path names. With no arguments, it changes to your home |
| directory. |
| ls: lists all files in the directory named. If no directory is named, |
| it lists the files of the current working directory |
| rm: deletes the file named |
| mv: renames the file named |
| cp: copies the file named |
| mkdir: makes a new directory |
| rmdir: deletes a directory. All files must have been first removed. |
| more: pages the file named so that the file appears on your screen one |
| page at a time. |
| cat: shows the whole file to you at once |
| head: shows you the first several lines of a file |
| tail: shows you the last several lines of a file |
| ed: allows you to edit a file using the mud editor |
| |
| 1.3 Chapter Summary |
| UNIX uses a heirarchical file structure with the root of the tree being |
| named /. Other directories branch off from that root directory and |
| in turn have their own sub-directories. All directories may contain |
| directories and files. Directories and files are referred to either |
| by their absolute name, which always begins with /, or by their relative |
| name which gives the file's name relative to a particular directory. |
| In order to get around in the UNIX files structure, you have the |
| typical UNIX commands for listing files, your current directory, etc. |
| On your mud, all of the above commands should have detailed help commands |
| to help you explore exactly what they do. In addition, there should |
| be a very detailed file on your mud's editor. If you are unfamiliar |
| with ed, you should go over this convoluted file. |