The following table is for those who know exactly what they want to do when they sit down in front of a terminal and need a lead on the corresponding UNIX command/utility. Common computing tasks in the left-hand column, and the conforming UNIX command/utility in the right-hand column. Note that the left-hand column is alphabetized by bold-face keywords.
| If you want to... | Use the UNIX command/utility... |
|---|---|
| append other files to an existing file | cat |
| create a tape archive | tar, cpio |
| search for ASCII strings within binary files | strings |
| search and replace ASCII characters | tr |
| create a tape backup | tar, cpio |
| print a 10-character banner | banner |
| start the Bourne shell | sh |
| start the C shell | csh |
| perform math calculations | bc, dc |
| display current month in calendar form | cal |
| call another terminal | ct |
| call another UNIX system | cu |
| cancel jobs scheduled with the at command | atrm |
| cancel print job | cancel |
| chat with another user on the network | talk, ytalk |
| calculate a file's checksum | sum |
| clear the screen | clear |
| display a column from a sorted file | cut |
| strip column-formatting commands | col |
| combine presorted files with a common field | join |
| combine several files into a new file | cat |
| run command at a specific time | at |
| run a series of commands | batch |
| time a command | time, timex |
| compare contents of two directories | dircmp |
| compare contents of two presorted files | comm |
| compare three files to see if they are different | diff3 |
| compare two files and report on differing lines | diff |
| compare two files and return differing lines | bdiff |
| compare two files to see if they are different | cmp |
| compare two files and report differences and commonalities | sdiff |
| compile C programs | gcc |
| compile C++ programs | g++ |
| compress a file | compress, pack |
| copy a file | cat, cp |
| copy files to and from networked remote systems | rcp |
| copy files to and from remote UNIX system | uucp |
| count the number of words in text file | wc |
| create a new text file | cat, vi, ex, joe, pico |
| change current directory | cd |
| stop a current process | kill |
| display date and time | date |
| change a file's date to the current date | touch |
| decode file after communications | uudecode |
| delete a file | rm |
| create a directory | mkdir |
| display disk space used by a directory | du |
| generate a directory listing | ls |
| change current working directory | cd |
| remove a directory | rmdir |
| return current working directory | pwd |
| compare the contents of two directories | dircmp |
| display free or total disk space | df |
| display disk space used by a directory | du |
| display a file | cat, page |
| display a file one screen at a time | more |
| display first ten lines of a file | head |
| display last ten lines of a file | tail |
| display packed files | pcat |
| edit a text file | vi, ed, pico, joe |
| send electronic mail | mail, mailx, elm, pine |
| send return electronic mail when you're one vacation | vacation |
| notify you when electronic mail arrives | notify |
| encode file before communications | uuencode |
| encrypt a file | crypt |
| display or set environment variables | env |
| format equations | eqn, neqn |
| erase a file | rm |
| exit | exit |
| copy a file | cat, cp |
| create a new text file | cat, vi |
| change a file's date to the current date | touch |
| display a file | cat, page |
| display a file one screen at a time | more |
| display first ten lines of a file | head |
| display last ten lines of a file | tail |
| edit a file | vi, ed |
| encrypt a file | crypt |
| erase a file | rm |
| find a file | find |
| format a structured file | awk, nawk |
| send output to file as well as screen | tee |
| change ownership of file | chown |
| move a file or multiple files | mv |
| display a column from a sorted file | cut |
| sort a file | sort |
| sort a structured file | awk, nawk |
| search a structured file | awk, nawk, grep |
| split a file into smaller files | csplit, split |
| determine file type | file |
| change file-access permissions | chmod |
| create or determine default file-access permissions | umask |
| append other files to an existing file | cat |
| combine presorted files with a common field | join |
| compare contents of two presorted files | comm |
| compare three files to see if they are different | diff3 |
| compare two files and report on differing lines | diff |
| compare two files and return differing lines | bdiff |
| compare two files to see if they are different | cmp |
| display packed files | pcat |
| merge files side by side | paste |
| change group membership of files | chgrp |
| list files | ls |
| link files | ln |
| search for ASCII strings within binary files | strings |
| remove files | rm |
| find the full filename | basename |
| find a file | find |
| format equations | eqn, neqn |
| format tables | tbl |
| format text file | newform |
| format a structured file | awk, nawk |
| format text for laser printer | troff |
| format text for line printer | nroff |
| format text (right justify) | fmt |
| format text to specific width | fold |
| log in new group | newgrp |
| find what groups a user belongs to | groups |
| get help | man, apropos, whatis |
| display user ID | id |
| start Korn shell | ksh |
| insert line numbers in text file | nl |
| link files | ln |
| list files | ls |
| save a log of your current computing session | script |
| log in as another user | su |
| log in new group | newgrp |
| log in remote system | rlogin, telnet |
| log in system | login |
| print your log in name | logname |
| print logins to other remote systems | uulog |
| log off system | exit |
| run a command even after you log off the system | nohup |
| show who is logged on the system | who, rwho |
| run a command at a low priority | nice |
| send electronic mail | mail, mailx, elm, pine |
| send return electronic mail when your on vacation | vacation |
| notify you when mail arrives | notify |
| peform math calculations | bc, dc |
| merge files side by side | paste |
| send message to all users loffed on the system | wall |
| turn on/off the ability to receive messages from other users | mesg |
| move a file or multiple files | mv |
| display system news | news |
| show status of all machines on network | ruptime |
| run a command nicely (at a lower priority) | nice |
| send output to file as well as screen | tee |
| change ownership of file | chown |
| change group ownership of files | chgrp |
| pack a file | compress, pack |
| display packed files | pcat |
| set your password | passwd |
| pause before executing a command | sleep |
| lpr | |
| prepare a file for printing | pr |
| print a 10-character banner | banner |
| cancel print job | cancel |
| print jobs scheduled with at command | atq |
| show status of print requests | lpstat |
| start print spooler | lpsched |
| stop print spooler | lpshut |
| stop a current process | kill |
| show current processes | ps |
| quit | exit |
| schedule recurring tasks | crontab |
| start a remote shell on a remote system | rsh |
| copy files to and from remote system | rcp, uucp, ftp |
| log on remote system | telnet, rlogin |
| run a UNIX command on a remote system | uux |
| print logins to other remote systems | uulog |
| remove a directory | rmdir |
| remove files | rm |
| rename a file | mv |
| run a UNIX command on a remote system | uux |
| schedule personal events | calendar |
| schedule recurring tasks | crontab |
| search a structured file | awk, nawk, grep |
| search for text string | egrep, grep, fgrep |
| searh and replace ASCII characters | tr |
| sort a file | sort |
| sort a structured file | awk, nawk |
| check spelling in text file | spell |
| split a file into smaller files | csplit, split |
| display to standard output | echo |
| show status of all machines on the network | ruptime |
| search for text string | egrep, grep, fgrep |
| strip column-formatting commands | col |
| strip formatting commands | deroff |
| return UNIX system name | uname |
| display system news | news |
| list systems that you can communicate with | uuname |
| format tables | tbl |
| set tabs | tabs |
| create a tape backup | tar, cpio |
| display terminal information | tput |
| display terminal options | tty |
| set terminal configuration | stty |
| check spelling in text file | spell |
| format text file | newform |
| format text for laser printer | troff |
| format text for line printer | nroff |
| format text (right justify) | fmt |
| format text to specific width | fold |
| insert line numbers in text file | nl |
| create a new text file | cat, vi, pico |
| search for text string | egrep, grep, fgrep |
| display date and time | date |
| run command at specific time | at |
| time a command | time, timex |
| determine file type | file |
| uncompress a file | uncompress |
| unpack a file | unpack |
| display user ID | id |
| list users | listusers |
| display information about other users on the system | who |
| find information about other users on the system | finger |
| show status of uucp requests | uustat |
| send return mail when your on vacation | vacation |
| force shell to wait | wait |
| write message to other user on the network | write |
| count the nubmer of words in text file | wc |
| return the current working directory | pwd |