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  message  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 internationalization 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 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).

       LC_MESSAGES
              Determine  the  locale  that  should  be  used to affect the format and contents of
              diagnostic messages 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 consisting 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  environment   variable   because
       environment changes could produce 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 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 .