logname(P)                                           logname(P)





NAME
       logname - return the user's login name

SYNOPSIS
       logname

DESCRIPTION
       The logname utility shall write the user's login name to
       standard output. The login name shall be the string that
       would  be returned by the getlogin() function defined in
       the System Interfaces  volume  of  IEEE Std 1003.1-2001.
       Under the conditions where the getlogin() function would
       fail, the logname utility shall write a diagnostic  mes-
       sage  to  standard  error  and exit with a non-zero exit
       status.

OPTIONS
       None.

OPERANDS
       None.

STDIN
       Not used.

INPUT FILES
       None.

ENVIRONMENT VARIABLES
       The following environment  variables  shall  affect  the
       execution of logname:

       LANG   Provide a default value for the internationaliza-
              tion variables that are unset or null.  (See  the
              Base  Definitions volume of IEEE Std 1003.1-2001,
              Section 8.2, Internationalization  Variables  for
              the  precedence of internationalization variables
              used to determine  the  values  of  locale  cate-
              gories.)

       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).

       LC_MESSAGES
              Determine the  locale  that  should  be  used  to
              affect the format and contents of diagnostic mes-
              sages written to standard error.

       NLSPATH
              Determine the location of  message  catalogs  for
              the processing of LC_MESSAGES .


ASYNCHRONOUS EVENTS
       Default.

STDOUT
       The  logname  utility output shall be a single line con-
       sisting of the user's login name:


              "%s\n", <login name>

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 logname utility explicitly ignores the LOGNAME envi-
       ronment variable because environment changes could  pro-
       duce erroneous results.

EXAMPLES
       None.

RATIONALE
       The  passwd  file  is not listed as required because the
       implementation may have other  means  of  mapping  login
       names.

FUTURE DIRECTIONS
       None.

SEE ALSO
       id   ,   who   ,   the   System   Interfaces  volume  of
       IEEE Std 1003.1-2001, getlogin()

COPYRIGHT
       Portions of this text are reprinted  and  reproduced  in
       electronic  form  from  IEEE  Std  1003.1, 2003 Edition,
       Standard for Information Technology -- Portable  Operat-
       ing System Interface (POSIX), The Open Group Base Speci-
       fications Issue 6, Copyright (C) 2001-2003 by the Insti-
       tute  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.open-
       group.org/unix/online.html .



POSIX                         2003                   logname(P)
