NAME

       logger - log messages

SYNOPSIS

       logger string ...

DESCRIPTION

       The  logger  utility saves a message, in an unspecified manner and format, containing the string operands
       provided by the user. The messages are expected to be evaluated  later  by  personnel  performing  system
       administration tasks.

       It  is  implementation-defined  whether  messages  written  in  locales  other  than the POSIX locale are
       effective.

OPTIONS

       None.

OPERANDS

       The following operand shall be supported:

       string One of the string arguments whose contents are concatenated  together,  in  the  order  specified,
              separated by single <space>s.

STDIN

       Not used.

INPUT FILES

       None.

ENVIRONMENT VARIABLES

       The following environment variables shall affect the execution of logger:

       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.  (This means diagnostics from logger to the user or application, not
              diagnostic messages that the user is sending to the system administrator.)

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

ASYNCHRONOUS EVENTS

       Default.

STDOUT

       Not used.

STDERR

       The standard error shall be used only for diagnostic messages.

OUTPUT FILES

       Unspecified.

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

       This utility allows logging of information for later use by  a  system  administrator  or  programmer  in
       determining why non-interactive utilities have failed. The locations of the saved messages, their format,
       and  retention  period  are  all  unspecified.   There  is no method for a conforming application to read
       messages, once written.

EXAMPLES

       A batch application, running non-interactively, tries to read a configuration  file  and  fails;  it  may
       attempt to notify the system administrator with:

              logger myname: unable to read file foo. [timestamp]

RATIONALE

       The  standard  developers  believed  strongly  that  some method of alerting administrators to errors was
       necessary. The obvious example is a batch utility, running non-interactively, that is unable to read  its
       configuration  files  or  that  is  unable  to  create  or  write its results file. However, the standard
       developers did not wish to define the format or delivery mechanisms as they have historically  been  (and
       will  probably  continue  to be) very system-specific, as well as involving functionality clearly outside
       the scope of this volume of IEEE Std 1003.1-2001.

       The text with LC_MESSAGES about diagnostic  messages  means  diagnostics  from  logger  to  the  user  or
       application, not diagnostic messages that the user is sending to the system administrator.

       Multiple string arguments are allowed, similar to echo, for ease-of-use.

       Like  the  utilities mailx and lp, logger is admittedly difficult to test. This was not deemed sufficient
       justification to exclude these utilities from this volume of IEEE Std 1003.1-2001. It  is  also  arguable
       that they are, in fact, testable, but that the tests themselves are not portable.

FUTURE DIRECTIONS

       None.

SEE ALSO

       lp , mailx , write()

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                                             LOGGER(P)