Display the last lines of a file in Unix

Use the Unix command tail to read from standard input or a file and send the result to standard output (that is, your terminal screen). The format for using the tail command is:

 tail [ +-[number][lbcr] ] [file]

Everything in brackets is an optional argument. If you don't specify a filename, tail uses standard input.

Tail begins at distance +number from the beginning or -number from the end of the input. The number is counted in units of lines, blocks, or characters, according to the appended options -l, -b, or -c. When you don't specify a unit, tail operates based on lines.

Specifying -r causes tail to print lines from the end of the file in reverse order. The default for -r is to print the entire file this way. Specifying -f causes tail not to quit at the end of the file, but rather to reread the file repeatedly (useful for watching a "growing" file such as a log file).

For example, given a file containing the English alphabet with each letter on a separate line, the command:

 tail -3 alphabetfile

would report:

 x y z

You can use tail with pipes. For example, to see the sizes of the last few files in the current directory, you could enter at the Unix prompt:

 ls -l | tail

To save this information in a file in the current directory named mylist, at the Unix prompt, enter:

 ls -l | tail > mylist

For more detailed information on tail, consult the Unix manual page by entering at the prompt:

 man tail