This article by Brad Yoes is my personal cheat sheet on UNIX manipulation. I highly suggests you read it if you want a better understanding on how to use these UNIX commands.
Note: This cheat sheet page is still very much a work in progress. I’m not even half way through yet and my documentation is pretty sparse. I’ll add onto when I can and try making it more verbose.
Operators and Miscellaneous Stuff
|End of file||<ctrl-d>|
The cat command performs basic file manipulation.
|File creation||cat > foo.bar
Entering a line of text
Entering another line of text
|File appending||cat >> foo.barEntering a new line of text
|File Displaying||cat foo.bar|
|File Displaying with counted lines||cat -n foo.bar|
The nl command is useful in reading lines.
|Readline with regex||nl -b p^[E] foo.bar|
|Customizing readline deliminator||nl -s: foo.bar|
WC is a basic counting command
|Counting lines, words separated by whitespace, and total characters||wc foo.bar|
|Counting only lines||wc -l foo.bar|
|Counting only words separated by whitespace||wc -w foo.bar|
|Counting only characters||wc -c foo.bar|
Grep is a basic command for searching a file
|Searching a single file||grep Enter foo.bar|
|Searching multiply files||grep Enter foo.bar text.txt|
|Counting found matches||grep -c Enter foo.bar|
|Hiding file name output||grep -h Enter foo.bar|
|Displaying own matched file names||grep -l Enter foo.bar|
|Ignoring case search||grep -i enter foo.bar|
|Including line numbers||grep -n Enter foo.bar|
|Inverted searching||grep -v Unix foo.bar|
|Word matching||grep -w Enter foo.bar|
Streams And Pipes
Stream File Descriptors
Merging and Splitting Streams
|make –f build_example 2>&1 | tee build.log|
This example will make a copy of the file foo.bar
|cat < foo.bar > foo.bar.bak|
This example will insert line numbers into the foo.bar file
|cat foo.bar| nl|
Piping vs Redirection
You can do similar things with one or the other. This examples will have the same output.
|grep -i example < foo.bar|
|cat foo.bar | grep -i example|
You can do some nifty things with here-doc, ‘<<‘. The here-doc command will redirect text into a command or file.
|cat << EOF
> Hello World!
File Head and Tail
If you’re not first then you’re last. The head command is the beginning of a file and likewise the tail command is the end. The flags -n and -c are important here. To display a given amount of lines you can use -n and to display a given amount of characters in the file you use the -c.
|Displaying beginning lines with -n||head -n5 foo.bar|
|Displaying ending lines with -n||tail -n5 foo.bar|
|Displaying beginning characters with -c||head -c12 foo.bar|
|Displaying ending characters with -c||tail -c12 foo.bar|
The TR command is pretty useful. Normally, tr is used with two sets of characters, and replaces characters from the first set with characters from the second set.
|Remove carriage returns||tr -d ‘\r’ unixfile.txt|