uniq -- display unique lines of sorted fileuniq 
      display unique lines of sorted file Command
         SYNOPSIS DESCRIPTION Options EXAMPLES DIAGNOSTICS PORTABILITY 
        AVAILABILITY SEE ALSO 




SYNOPSIS
uniq [-c|-d|-u] [-f number1] [-s number2] [input_file [output_file]] 
uniq [-c|-d|-u] [-number] [+number] [input_file [output_file]] 



DESCRIPTION
uniq manipulates lines which occur more than once in a file. The file must be 
sorted, since uniq only compares adjacent lines. When you invoke this command 
with no options, it writes only one copy of each line in input_file to 
output_file. If you do not specify input_file or you specify -, uniq reads the 
standard input. If you do not specify output_file, uniq uses the standard 
output. 
Options
  -c  
  precedes each output line with the number of times that line occurred in the 
  input. 
  -d  
  displays only lines which are repeated (one copy of each line). 
  -f number1  
  ignores the first number1 fields when comparing lines. Blanks separate fields 
  in the input. 
  -s number2  
  ignores the first number2 characters when comparing lines. If you specify both 
  -s and -f, uniq ignores the first number2 characters after the first number1 
  fields. 
  -u  
  displays only those lines which are not repeated. 
You may choose only one of the -c, -d, or -u options. 
  -number  
  is an obsolete equivalent to -f number. 
  +number  
  is an obsolete equivalent to -s number. 



EXAMPLES
uniq
is a filter which prints one copy of each different line in its sorted input. 
uniq -f 2 -s 1
compares lines starting with the 2nd character of the 3rd field. 
uniq -d
outputs one instance of each repeated line in the input (and omits all unique 
lines). 



DIAGNOSTICS
Possible exit status values are: 
  0  
  Successful completion. 
  1  
  Failure due to any of the following: 
    — invalid command line option 
    — missing number after -f 
    — missing or invalid number after -s 
    — inability to open the input or output file 
  Missing character skip count  
  You specified -s but did not supply a number after the -s. 
  Missing number of fields to skip  
  You specified -f but did not supply a number after the -f. 
  field skip not a number in "string"  
  In a -number or +number construct, number wasn't valid. This could arise from 
  a typo when entering a - option. 



PORTABILITY
POSIX.2. x/OPEN Portability Guide 4.0. All UNIX systems. Windows Me. Windows NT 
4.0. Windows 2000. Windows XP. Windows Server 2003. 



AVAILABILITY
MKS Toolkit for Power Users
MKS Toolkit for System Administrators
MKS Toolkit for Developers
MKS Toolkit for Interoperability
MKS Toolkit for Professional Developers
MKS Toolkit for Enterprise Developers
MKS Toolkit for Enterprise Developers 64-Bit Edition
MKS AlertCentre




SEE ALSO
  Commands: 
  comm, sort