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NAME

       fmtmsg  -  display  a message in the specified format on standard error
       and/or a system console

SYNOPSIS

       #include <fmtmsg.h>

       int fmtmsg(long classification, const char *label, int severity,
              const char *text, const char *action, const char *tag);

DESCRIPTION

       The fmtmsg() function shall display  messages  in  a  specified  format
       instead of the traditional printf() function.

       Based  on  a message’s classification component, fmtmsg() shall write a
       formatted message either to standard error, to the console, or to both.

       A formatted message consists of up to five components as defined below.
       The component classification is not part of a message displayed to  the
       user,  but defines the source of the message and directs the display of
       the formatted message.

       classification
              Contains the sum of  identifying  values  constructed  from  the
              constants  defined below. Any one identifier from a subclass may
              be used in combination with a single identifier from a different
              subclass.  Two or more identifiers from the same subclass should
              not be used together, with the exception of identifiers from the
              display subclass. (Both display subclass identifiers may be used
              so that messages can be displayed to both standard error and the
              system console.)

       Major Classifications

              Identifies the source of the condition. Identifiers are: MM_HARD
              (hardware), MM_SOFT (software), and MM_FIRM (firmware).

       Message Source Subclassifications

              Identifies  the  type  of  software  in  which  the  problem  is
              detected.    Identifiers  are:  MM_APPL  (application),  MM_UTIL
              (utility), and MM_OPSYS (operating system).

       Display Subclassifications

              Indicates where the message is to be displayed. Identifiers are:
              MM_PRINT  to  display  the message on the standard error stream,
              MM_CONSOLE to display the message on the system console. One  or
              both identifiers may be used.

       Status Subclassifications

              Indicates   whether   the   application  can  recover  from  the
              condition.   Identifiers  are:  MM_RECOVER   (recoverable)   and
              MM_NRECOV (non-recoverable).

       An  additional  identifier, MM_NULLMC, indicates that no classification
       component is supplied for the message.

       label  Identifies the source of the message. The format is  two  fields
              separated  by  a  colon.  The first field is up to 10 bytes, the
              second is up to 14 bytes.

       severity
              Indicates the seriousness of the condition. Identifiers for  the
              levels of severity are:

       MM_HALT
              Indicates  that  the  application has encountered a severe fault
              and is halting. Produces the string "HALT" .

       MM_ERROR
              Indicates that the application has detected  a  fault.  Produces
              the string "ERROR" .

       MM_WARNING
              Indicates a condition that is out of the ordinary, that might be
              a problem, and should be watched. Produces the string  "WARNING"
              .

       MM_INFO
              Provides  information  about  a  condition that is not in error.
              Produces the string "INFO" .

       MM_NOSEV
              Indicates that no severity level is supplied for the message.

       text   Describes the error condition that  produced  the  message.  The
              character  string  is  not  limited  to  a specific size. If the
              character  string  is  empty,  then   the   text   produced   is
              unspecified.

       action Describes  the  first  step  to  be  taken in the error-recovery
              process.  The fmtmsg() function precedes the action string  with
              the  prefix:  "TO  FIX:" . The action string is not limited to a
              specific size.

       tag    An identifier that  references  on-line  documentation  for  the
              message.   Suggested  usage is that tag includes the label and a
              unique identifying number. A sample tag is "XSI:cat:146" .

       The  MSGVERB  environment  variable  (for  message   verbosity)   shall
       determine  for  fmtmsg()  which message components it is to select when
       writing messages to standard error. The value of  MSGVERB  shall  be  a
       colon-separated  list  of optional keywords. Valid keywords are: label,
       severity, text, action, and tag. If MSGVERB contains a  keyword  for  a
       component  and the component’s value is not the component’s null value,
       fmtmsg() shall include that component in the message when  writing  the
       message  to standard error. If MSGVERB does not include a keyword for a
       message component, that component shall not be included in the  display
       of  the  message.   The keywords may appear in any order. If MSGVERB is
       not defined, if its value is the null string, if its value  is  not  of
       the  correct  format,  or  if it contains keywords other than the valid
       ones listed above, fmtmsg() shall select all components.

       MSGVERB shall determine which components are selected  for  display  to
       standard  error.  All  message  components shall be included in console
       messages.

RETURN VALUE

       The fmtmsg() function shall return one of the following values:

       MM_OK  The function succeeded.

       MM_NOTOK
              The function failed completely.

       MM_NOMSG
              The function was unable to generate a message on standard error,
              but otherwise succeeded.

       MM_NOCON
              The  function  was  unable  to  generate  a console message, but
              otherwise succeeded.

ERRORS

       None.

       The following sections are informative.

EXAMPLES

        1. The following example of fmtmsg():

           fmtmsg(MM_PRINT, "XSI:cat", MM_ERROR, "illegal option",
           "refer to cat in users reference manual", "XSI:cat:001")

       produces a complete message in the specified message format:

              XSI:cat: ERROR: illegal option
              TO FIX: refer to cat in users reference manual XSI:cat:001

        2. When the environment variable MSGVERB is set as follows:

           MSGVERB=severity:text:action

       and Example 1 is used, fmtmsg() produces:

              ERROR: illegal option
              TO FIX: refer to cat in users reference manual

APPLICATION USAGE

       One or more message  components  may  be  systematically  omitted  from
       messages  generated  by  an  application by using the null value of the
       argument for that component.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       printf()  ,  the  Base  Definitions  volume  of   IEEE Std 1003.1-2001,
       <fmtmsg.h>

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 .