HEAD and TAIL funtionality of terminal in Node.js

tead is a command in shell(terminal) to print first n lines of referenced file.

• synopsis head -nN filename tail is a command in shell(terminal) to print first n lines of referenced file.
• synopsis tail -nN filename

Input for the file could be in any one of the following syntax.

• node head.js file.txt -> print first 10 lines of the given file.

• node head.js NOFILE -> Print "head: cannot open 'NOFILE' for reading: No such file or directory".

• node head.js -N file.txt -> Print first N lines of the given file.

• node head.js -N NOFILE -> Print "head: cannot open 'NOFILE' for reading: No such file or directory".

• node head.js -a file.txt -> Print "head: invalid number of lines: 'a'".

• node head.js -nN file.txt -> Print first N lines of the given file.

• node head.js -nN NOFile -> Print "head: cannot open 'NOFILE' for reading: No such file or directory".

• node head.js -na file.txt -> Print "head: invalid number of lines: 'a'".

• node tail.js file.txt -> print last 10 lines of the given file.

• node tail.js NOFILE -> Print "tail: cannot open 'NOFILE' for reading: No such file or directory".

• node tail.js -N file.txt -> Print last N lines of the given file.

• node tail.js -N NOFILE -> Print "tail: cannot open 'NOFILE' for reading: No such file or directory".

• node tail.js -a file.txt -> Print "tail: invalid number of lines: 'a'".

• node tail.js -nN file.txt -> Print last N lines of the given file.

• node tail.js -nN NOFile -> Print "tail: cannot open 'NOFILE' for reading: No such file or directory".

• node tail.js -na file.txt -> Print "tail: invalid number of lines: 'a'".