| Command/Syntax | What it will do |
|---|---|
| gawk [options] file | scan for patterns in a file and process the results |
| cat [options] file | concatenate (list) a file |
| cd [directory] | change directory |
| chgrp [options] group file | change the group of the file |
| chmod [options] file | change file or directory access permissions |
| chown [options] owner file | change the ownership of a file; can only be done by the superuser |
| cmp [options] file1 file2 | compare two files and list where differences occur (text or binary files) |
| compress [options] file | compress file and save it as file.Z |
| cp [options] file1 file2 | copy file1 into file2; file2 shouldn't already exist. This command creates or overwrites file2. |
| cut (options) [file(s)] | cut specified field(s)/character(s) from lines in file(s) |
| date [options] | report the current date and time |
| dd [if=infile] [of=outfile] [operand=value] | copy a file, converting between ASCII and EBCDIC or swapping byte order, as specified |
| diff [options] file1 file2 | compare the two files and display the differences (text files only) |
| df [options] [resource] | report the summary of disk blocks and inodes free and in use |
| du [options] [directory or file] | report amount of disk space in use |
| echo [text string] | echo the text string to stdout |
| emacs [options] file | full-screen editor |
| expr arguments | evaluate the arguments. Used to do arithmetic, etc. in the shell. |
| file [options] file | classify the file type |
| find directory [options] [actions] | find files matching a type or pattern |
| grep [options] 'search string' argument
egrep [options] 'search string' argument fgrep [options] 'search string' argument |
search the argument (in this case probably a file) for all occurrences of the search string, and list them. |
| gzip [options] file
gunzip [options] file zcat [options] file |
compress or uncompress a file. Compressed files are stored with a .gz ending |
| head [-number] file | display the first 10 (or number of) lines of a file |
| hostname | display or set (super-user only) the name of the current machine |
| kill [options] [-SIGNAL] [pid#] [%job] | send a signal to the process with the process id number (pid#) or job control number (%n). The default signal is to kill the process. |
| ln [options] source_file target | link the source_file to the target |
| lpq [options]
lpstat [options] |
show the status of print jobs |
| lpr [options] file
lp [options] file |
print to defined printer |
| lprm [options]
cancel [options] |
remove a print job from the print queue |
| ls [options] [directory or file] | list directory contents or file permissions |
| mail [options] [user]
mailx [options] [user] Mail [options] [user] |
simple email utility available on Unix systems. Type a period as the first character on a new line to send message out, question mark for help. |
| man [options] command | show the manual (man) page for a command |
| mkdir [options] directory | make a directory |
| more [options] file
less [options] file pg [options] file |
page through a text file |
| mv [options] file1 file2 | move file1 into file2 |
| paste [options] file | paste field(s) onto the lines in file |
| pr [options] file | filter the file and print it on the terminal |
| ps [options] | show status of active processes |
| pwd | print working (current) directory |
| rm [options] file | remove (delete) a file or directory (-r recursively deletes the directory and its contents) (-i prompts before removing files) |
| rmdir [options] directory | remove a directory |
| script file | saves everything that appears on the screen to file until exit is executed |
| sed [options] file | stream editor for editing files from a script or from the command line |
| sftp [user@] host [:file [file]] |
transfer file(s) using secure file transfer protocol |
| sort [options] file | sort the lines of the file according to the options chosen |
| source file
. file |
read commands from the file and execute them in the current shell. source: C shell, .: Bourne shell. |
| ssh [-l user] hostname | secure shell connect to another machine |
| strings [options] file | report any sequence of 4 or more printable characters ending in <NL> or <NULL>. Usually used to search binary files for ASCII strings. |
| stty [options] | set or display terminal control options |
| tail [options] file | display the last few lines (or parts) of a file |
| tar key[options] [file(s)] | tape archiver--refer to man pages for details on creating, listing, and retrieving from archive files. Tar files can be stored on tape or disk. |
| tee [options] file | copy stdout to one or more files |
| touch [options] [date] file | create an empty file, or update the access time of an existing file |
| tr [options] string1 string2 | translate the characters in string1 from stdin into those in string2 in stdout |
| uncompress file.Z | uncompress file.Z and save it as a file |
| uniq [options] file | remove repeated lines in a file |
| vi [options] file | visual, full-screen editor |
| wc [options] [file(s)] | display word (or character or line) count for file(s) |
| whereis [options] command | report the binary, source, and man page locations for the command named |
| which command | reports the path to the command or the shell alias in use |
| who or w | report who is logged in and what processes are running |
| zcat file.Z | concatenate (list) uncompressed file to screen, leaving file compressed on disk |
Adapted in part from the following source, in agreement with the listed copyright statements: