unix指令汇总(英文版).doc

Unix Command Summary See the Unix?tutorial?for a leisurely, self-paced introduction on how to use the commands listed below. For more documentation on a command, consult a good book, or use the man pages. For example, for more information on?grep, use the command?man grep. Contents cat? for creating and displaying short files chmod? change permissions cd? change directory cp? for copying files date? display date echo? echo argument ftp? connect to a remote machine to download or upload files grep? search file head? display first part of file ls? see what files you have lpr? standard print command (see also?print?) more? use to read files mkdir? create directory mv? for moving and renaming files ncftp? especially good for downloading files via anonymous?ftp. print? custom print command (see also?lpr?) pwd? find out what directory you are in rm? remove a file rmdir? remove directory rsh? remote shell setenv? set an environment variable sort? sort file tail? display last part of file tar? create an archive, add or extract files telnet? log in to another machine wc? count characters, words, lines cat This is one of the most flexible Unix commands. We can use to create, view and concatenate files. For our first example we create a three-item English-Spanish dictionary in a file called dict. % cat dict red rojo green verde blue azul control-D % control-D stands for hold the control key down, then tap d. The symbol??tells the computer that what is typed is to be put?into?the file?dict. To view a file we use?cat?in a different way: % cat dict red rojo green verde blue azul % If we wish to add text to an existing file we do this: % cat dict white blanco black negro control-D % Now suppose that we have another file?tmp?that looks like this: % cat tmp cat gato dog perro % Then we can join?dict?and?tmp?like this: % cat dict tmp dict2 We could check the number of lines in the new file like this