Unix 3 -- Simple Unix Commands

Math 10 -- D. C. Smolarski, S.J.
Santa Clara University, Department of Mathematics and Computer Science

Contents

• Resetting Terminal Type
• Keyboard Keys
• Simple Commands

Resetting Terminal Type

If one uses telnet from non-X-Windows machine, it is best to reset the terminal either when prompted at login (if using the C-shell) to vt220 or by using the C-shell command:

     set term=vt220

Keyboard Keys

In particular, there are differences as to which key to use to erase the previously typed characters.

Part of the confusion is that some systems redefine the "rubout" feature upon login and do this differently than other systems.

In general, on the HP system, one should use the backspace key to erase the previously written character and not the Delete key (which will produce the character "^?").

On some other Unix systems, one needs to invoke a <ctrl>h to force an erasure.

Please note, once again, that on other Unix systems, the key or key combination used to erase a character may be different!

Simple Commands

• ls
  lists the filenames in the current directory. Optionally, one can indicate a filename or part of a filename with the * wildcard.
• ls -a
  lists the filenames in the current directory including those usually hidden, i.e., those with a period as the initial character.
• ls -l
  lists the filenames in the current directory in long format, i.e., with protection, ownership, and date of last modification. (Note: ls -al gives both the long format and all hidden files since both "switches" are included together.)
• cd
  change to the home directory.
• cd directory_name
  changes directory to the directory listed.
• mkdir directory_name
  makes a new subdiretory with the name directory_name.
• rmdir directory_name
  deletes (ReMoves) the subdiretory with the name directory_name.
• pwd
  indicates the present working directory.
• fg
  restarts a job suspended by <cntl>z.
• more filename
  types the filename indicated on the screen
• rm filename
  deletes the filename indicated.
• compress filename
  compresses the filename indicated.
• uncompress filename
  uncompresses the filename indicated.
• lp filename
  prints the filename indicated on the line printer. By default, math prints to the O'Connor printer and the printout will include a header page. (On some systems lpr also works.)

  ---

  To print to one of the Kenna lab printers or one of the Orradre lab printers, you must include a "switch" before the filename to indicate the destination. The "switch" consists of two characters -d followed by one of the following: kenna1 kenna2 orradre1 orradre2.

  Thus, for example, to print the file mp1ou.output to one of the Kenna printers, one types:

       math 23: lp -d kenna1 mp1ou.out
  

  and to print the file mp1ou.output to one of the Orradre printers, one types:

          math 24: lp -d orradre1 mp1ou.out
  

  (The "-d" "switch" indicate the "destination" printer that the file should be sent to. There are two printers in Kenna and Orradre, designated "kenna1" and "kenna2" and similarly two in Orradre. You can use any of them.)

  ---

• man command
  invokes the on-line manual for the command command.
• cat filename
  concatenates filename. If there is no other argument, filename appears on the screen. If one want to combine (i.e., concatenate) two files into a third, one invokes:
  cat file1 file2 > file3
• grep string filename
  locates the places where string occurs in file filename.
• man command
  invokes the on-line manual for the command command.
• mv file1 file2
  renames (i.e., moves) file1 to file2 (a file can be moved to another directory if desired.
• cp file1 file2
  copies file1 to file2.
• passwd
  initiates the program for changing your password.
• alias string1 string2
  make string1 an alias for string2 no matter whether string2 is an email address or system command with switches. Such aliases may be included in a .login file or a .mailrc file.
• jobs
  reports on the names of suspended jobs.
• finger
  indicates current users. finger username gives the status of username. On the HP system, finger -R indicates the location from which a user has logged into the system either by domain name or IP address.

  In the individual format, if username has a .plan file and a .project file in the home directory, the finger command will also print that information out for the person invoking it.

• printenv
  indicates the values of all the ENVIRONMENT variables.

This page is maintained by Dennis C. Smolarski, S.J. dsmolarski@math.scu.edu
© Copyright 1998, 1999, 2000 Dennis C. Smolarski, SJ, All rights reserved.
Last changed: 21 September 2000.