NAME

       fg - run jobs in the foreground

SYNOPSIS

       fg [job_id]

DESCRIPTION

       If  job  control  is  enabled (see the description of set -m), the fg utility 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 environment''; 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 operand 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  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 fg utility shall write the command line of the job to standard output in the following format:

              "%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 characteristics 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 maintain 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()

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                                                 FG(P)