Sort-Merge Files

     $sort [–cmu] [–ofile] [–yk] [–zn][–dfiMnr][–btc]
              [ +pos1 –pos2  ]] [ files ]

Description:

The sort command sorts lines from files.

Options:

–b	ignore leading tabs and spaces
–c	check that the input is in sorted order
–d	sort in dictionary order; only letters, digits, and white-space are significant in comparisons
–f	sort upper and lower case letters together
–i	ignore non-printable characters
–m	merge already sorted files
–M	sort as months. The first three non-blank characters are converted to upper case and compared. (implies –b)
–n	sort by numerical value; blanks, minus signs, and decimal points can also be given (implies –b)
–ofile	send output to file (default standard output)
–r	reverse the sorting order
–tc	set the field separator to c
–u	display only one occurrence of duplicate lines
–y[k]	use k kilobytes of memory to sort (default max)
–zn	use n bytes of buffer for long lines
files	read standard input if files is – or no files given
+pos1 [ –pos2] sort from pos1 to pos2.
	If pos2 is not specified, sort from pos1 to the end of line. The format for pos1 and pos2 is: m[.n] [bdfinr]
	m	m fields from start of line (default 0)
	n	n characters from start of field (default 0)
	bdfinr	option applies to the specified key only

Translate Characters

    $tr [–cds] [string1] [string2]

Description:

The tr command copies standard input to output and translates characters from string1 to characters in string2.

Options:

–c	translate characters not in string1
–d	delete characters in string1 from input
–s	truncate repeated characters from string2

Strings:

[a–z]	specifies range of characters from a to z
[c*n]	specifies n repetitions of c. If the first digit in n is 0, n interpreted as octal. (default decimal)

Report Duplicate Lines

    $uniq [ –udc [ +n ] [ –n ] ] [ file1 [ file2 ] ]

Description:

The uniq command removes duplicate adjacent lines from file1 and places the output in file2.

Options:

–c	display a count of duplicate lines also
–d	display only duplicate lines once
–u	display only unique lines from the original file
–n	skip first n fields from start of line
+n	skip first n characters from the start of field