[ Pobierz całość w formacie PDF ]
.Ask for assistance if you didn't knowwhat the command did.Some messages will alert you of bugs.Some messages are not bugs.Check Section 3.4 andany other documentation to make sure they aren't normal informational messages.For instance,1Ainternational discussion group on Usenet, which talks about administring Unix computers.12.3.NOT YOUR FAULT 127messages like disk full" or lp0 on re" aren't software problems, but something wrong with yourhardware|not enough disk space, or a bad printer.If you can't nd anything about a program, it is a bug in the documentation, and you shouldcontact the author of that program and o er to write it yourself.If something is incorrect in existingdocumentation2, it is a bug with that manual.If something appears incomplete or unclear in themanual, that is a bug.If you can't beat gnuchess at chess, it is a aw with your chess algorithm, but not necessarily abug with your brain.12.3.2 Reporting a BugAfter you are sure you found a bug, it is important to make sure that your information gets to theright place.Try to nd what program is causing the bug|if you can't nd it, perhaps you couldask for help in comp.os.linux.help or comp.unix.misc.Once you nd the program, try to readthe manual page to see who wrote it.The preferred method of sending bug reports in the Linux world is via electronic mail.If youdon't have access to electronic mail, you might want to contact whoever you got Linux from|eventually, you're bound to encounter someone who either has electronic mail, or sells Linux com-mercially and therefore wants to remove as many bugs as possible.Remember, though, that no oneis under any obligation to x any bugs unless you have a contract!When you send a bug report in, include all the information you can think of.This includes:A description of what you think is incorrect.For instance, I get 5 when I compute 2+2" orIt says segmentation violation -- core dumped." It is important to say exactly what ishappening so the maintainer can x your bug!Include any relevant environment variables.The version of your kernel see the le proc version and your system libraries see thedirectory lib|if you can't decipher it, send a listing of lib.How you ran the program in question, or, if it was a kernel bug, what you were doing at thetime.All peripheral information.For instance, the command w may not be displaying the currentprocess for certain users.Don't just say, w doesn't work when for a certain user".The bugcould occur because the user's name is eight characters long, or when he is logging in over thenetwork.Instead say, w doesn't display the current process for user greenfie when he logsin over the network."And remember, be polite.Most people work on free software for the fun of it, and becausethey have big hearts.Don't ruin it for them|the Linux community has already disillusionedtoo many developers, and it's still early in Linux's life!2Especially this one!128 CHAPTER 12.ERRORS, MISTAKES, BUGS, AND OTHER UNPLEASANTRIESAppendix AIntroduction to Vivi pronounced vee eye" is really the only editor you can nd at almost every Unix installation.It was originally written at the University of California at Berkeley and versions can be found italmost every vendor's edition of Unix, including Linux.It is initially somewhat hard to get usedto, but it has many powerful features.In general, we suggest that a new user learn Emacs, whichis generally easier to use.However, people who will use more than one platform or nd they dislikeEmacs may want to try to learn vi.A brief historical view of vi is necessary to understand how the key k can mean move cursorup one line and why there are three di erent modes of use.If you are itchy to learn the editor, thenthe two tutorials will guide you from being a raw beginner, through to having enough knowledgeof the command set you are ever likely to need.The chapter also incorporates a command guide,which makes a useful reference to keep by the terminal.Even if vi does not become your regular text editor, the knowledge of its use is not wasted.It isalmost certain that the Unix system you are using will have some variant of the vi editor.It may benecessary to use vi while installing another editor, such as Emacs.Many Unix tools, applicationsand games use a subset of the vi command set.A.1 A Quick History of ViEarly text editors were line oriented and typically were used from dumb printing terminals.Atypicaleditor that operates in this mode is Ed.The editor is powerful and e cient, using a very smallamount of computer resources, and worked well with the display equipment of the time.vi o ersthe user a visual alternative with a signi cantly expanded command set compared with ed.vi as we knowit today started as the line editor ex.In fact ex is seen as a special editing modeof vi, although actually the converse is true.The visual component of ex can be initiated from thecommand line by using the vi command, or from within ex.The ex vi editor was developed at the University of California at Berkeley by William Joy [ Pobierz całość w formacie PDF ]