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WC(1P)                     POSIX Programmer's Manual                    WC(1P)

PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux
       implementation of this interface may differ (consult the  corresponding
       Linux  manual page for details of Linux behavior), or the interface may
       not be implemented on Linux.
NAME
       wc - word, line, and byte or character count
SYNOPSIS
       wc [-c|-m][-lw][file...]
DESCRIPTION
       The wc utility shall read one or more  input  files  and,  by  default,
       write  the  number  of  <newline>s,  words, and bytes contained in each
       input file to the standard output.
       The utility also shall write a total count for all named files, if more
       than one input file is specified.
       The  wc utility shall consider a word to be a non-zero-length string of
       characters delimited by white space.
OPTIONS
       The wc  utility  shall  conform  to  the  Base  Definitions  volume  of
       IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.
       The following options shall be supported:
       -c     Write  to  the standard output the number of bytes in each input
              file.
       -l     Write to the standard output the number of  <newline>s  in  each
              input file.
       -m     Write  to  the  standard output the number of characters in each
              input file.
       -w     Write to the standard output the number of words in  each  input
              file.

       When  any  option  is  specified,  wc shall report only the information
       requested by the specified options.
OPERANDS
       The following operand shall be supported:
       file   A pathname of an input file. If no file operands are  specified,
              the standard input shall be used.

STDIN
       The  standard  input  shall be used only if no file operands are speci-
       fied. See the INPUT FILES section.
INPUT FILES
       The input files may be of any type.
ENVIRONMENT VARIABLES
       The following environment variables shall affect the execution of wc:
       LANG   Provide a default value for the  internationalization  variables
              that  are  unset  or  null.  (See the Base Definitions volume of
              IEEE Std 1003.1-2001, Section  8.2,  Internationalization  Vari-
              ables  for the precedence of internationalization variables used
              to determine the values of locale categories.)
       LC_ALL If set to a non-empty string value, override the values  of  all
              the other internationalization variables.
       LC_CTYPE
              Determine  the  locale  for  the  interpretation of sequences of
              bytes of text data as characters (for  example,  single-byte  as
              opposed  to  multi-byte characters in arguments and input files)
              and which characters are defined as white space characters.
       LC_MESSAGES
              Determine the locale that should be used to  affect  the  format
              and  contents  of  diagnostic messages written to standard error
              and informative messages written to standard output.
       NLSPATH
              Determine the location of message catalogs for the processing of
              LC_MESSAGES .

ASYNCHRONOUS EVENTS
       Default.
STDOUT
       By  default,  the standard output shall contain an entry for each input
       file of the form:

              "%d %d %d %s\n", <newlines>, <words>, <bytes>, <file>
       If the -m option is specified, the number of characters  shall  replace
       the <bytes> field in this format.
       If  any  options  are specified and the -l option is not specified, the
       number of <newline>s shall not be written.
       If any options are specified and the -w option is  not  specified,  the
       number of words shall not be written.
       If  any  options  are specified and neither -c nor -m is specified, the
       number of bytes or characters shall not be written.
       If no input file operands are specified, no name shall be  written  and
       no <blank>s preceding the pathname shall be written.
       If  more  than  one input file operand is specified, an additional line
       shall be written, of the same format as the other  lines,  except  that
       the  word  total  (in  the  POSIX locale) shall be written instead of a
       pathname and the total of each column shall be written as  appropriate.
       Such an additional line, if any, is written at the end of the output.
STDERR
       The standard error shall be used only for diagnostic messages.
OUTPUT FILES
       None.
EXTENDED DESCRIPTION
       None.
EXIT STATUS
       The following exit values shall be returned:
        0     Successful completion.
       >0     An error occurred.

CONSEQUENCES OF ERRORS
       Default.
       The following sections are informative.
APPLICATION USAGE
       The  -m  option is not a switch, but an option at the same level as -c.
       Thus, to produce the full default output with character counts  instead
       of bytes, the command required is:

              wc -mlw
EXAMPLES
       None.
RATIONALE
       The  output file format pseudo- printf() string differs from the System
       V version of wc:

              "%7d%7d%7d %s\n"
       which produces possibly ambiguous and unparsable results for very large
       files, as it assumes no number shall exceed six digits.
       Some  historical implementations use only <space>, <tab>, and <newline>
       as word separators. The equivalent  of  the  ISO C  standard  isspace()
       function is more appropriate.
       The  -c  option  stands  for  "character"  count, even though it counts
       bytes. This stems from the sometimes  erroneous  historical  view  that
       bytes  and  characters are the same size. Due to international require-
       ments, the -m option (reminiscent of "multi-byte") was added to  obtain
       actual character counts.
       Early  proposals  only specified the results when input files were text
       files. The current specification more closely matches historical  prac-
       tice.  (Bytes,  words,  and  <newline>s  are counted separately and the
       results are written when an end-of-file is detected.)
       Historical implementations of the wc utility only accepted one argument
       to  specify  the options -c, -l, and -w. Some of them also had multiple
       occurrences of an option cause the corresponding count  to  be  written
       multiple times and had the order of specification of the options affect
       the order of the fields on output,  but  did  not  document  either  of
       these.   Because  common  usage either specifies no options or only one
       option, and because none of this was documented, the  changes  required
       by this volume of IEEE Std 1003.1-2001 should not break many historical
       applications (and do not break any historical conforming applications).
FUTURE DIRECTIONS
       None.
SEE ALSO
       cksum
COPYRIGHT
       Portions of this text are reprinted and reproduced in  electronic  form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
       event of any discrepancy between this version and the original IEEE and
       The Open Group Standard, the original IEEE and The Open Group  Standard
       is  the  referee document. The original Standard can be obtained online
       at http://www.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                               WC(1P)