SYNOPSIS
       fg [job_id]

DESCRIPTION
       If job control is enabled (see the description of set -m), the fg util-
       ity shall move a background job from the current environment (see Shell
       Execution Environment ) into the foreground.

       Using fg to place a job into the foreground shall remove its process ID
       from the list of those "known in the current shell  execution  environ-
       ment''; see Asynchronous Lists .

OPTIONS
       None.

OPERANDS
       The following operand shall be supported:

       job_id Specify  the job to be run as a foreground job. If no job_id op-
              erand is given, the job_id for the job that  was  most  recently
              suspended,  placed in the background, or run as a background job
              shall be used. The format of job_id is  described  in  the  Base
              Definitions  volume  of IEEE Std 1003.1-2001, Section 3.203, Job
              Control Job ID.


STDIN
       Not used.

INPUT FILES
       None.

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

       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).

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


              "%s\n", <command>

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
       If job control is disabled, the fg utility shall exit with an error and
       no job shall be placed in the foreground.

       The following sections are informative.

APPLICATION USAGE
       The  fg  utility  does not work as expected when it is operating in its
       own utility execution  environment  because  that  environment  has  no
       applicable jobs to manipulate. See the APPLICATION USAGE section for bg
       . For this reason, fg is  generally  implemented  as  a  shell  regular
       built-in.

EXAMPLES
       None.

RATIONALE
       The   extensions   to   the   shell   specified   in   this  volume  of
       IEEE Std 1003.1-2001 have mostly been based on features provided by the
       KornShell.  The  job  control features provided by bg, fg, and jobs are
       also based on the KornShell. The standard developers examined the char-
       acteristics  of  the C shell versions of these utilities and found that
       differences exist. Despite widespread use of the C shell, the KornShell
       versions were selected for this volume of IEEE Std 1003.1-2001 to main-
       tain a degree of uniformity with the rest  of  the  KornShell  features
       selected (such as the very popular command line editing features).

FUTURE DIRECTIONS
       None.

SEE ALSO
       Asynchronous Lists , Shell Execution Environment , bg , kill() , jobs ,
       wait()