JOBS(1P)						     POSIX Programmer's Manual							  JOBS(1P)

PROLOG

       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME

       jobs - display status of jobs in the current session

SYNOPSIS

       jobs [-l| -p][job_id...]

DESCRIPTION

       The jobs utility shall display the status of jobs that were started in the current shell environment; see Shell Execution Environment .

       When jobs reports the termination status of a job, the shell shall remove its process ID from the list of those "known in the current shell
       execution environment''; see Asynchronous Lists .

OPTIONS

       The jobs utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines.

       The following options shall be supported:

       -l     (The  letter  ell.)  Provide  more  information  about each job listed.  This information shall include the job number, current job,
	      process group ID, state, and the command that formed the job.

       -p     Display only the process IDs for the process group leaders of the selected jobs.

       By default, the jobs utility shall display the status of all stopped jobs, running background jobs and all jobs whose  status  has  changed
       and have not been reported by the shell.

OPERANDS

       The following operand shall be supported:

       job_id Specifies the jobs for which the status is to be displayed. If no job_id is given, the status information for all jobs shall be dis-
	      played. 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 jobs:

       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 and
	      informative messages written to standard output.

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

ASYNCHRONOUS EVENTS

       Default.

STDOUT

       If the -p option is specified, the output shall consist of one line for each process ID:

	      "%d
", <process ID>

       Otherwise, if the -l option is not specified, the output shall be a series of lines of the form:

	      "[%d] %c %s %s
", <job-number>, <current>, <state>, <command>

       where the fields shall be as follows:

       <current>
	      The character '+' identifies the job that would be used as a default for the fg or bg utilities; this  job  can  also  be  specified
	      using  the job_id %+ or "%%" . The character '-' identifies the job that would become the default if the current default job were to
	      exit; this job can also be specified using the job_id %-. For other jobs, this field is a <space>. At most one job can be identified
	      with  '+'  and at most one job can be identified with '-' . If there is any suspended job, then the current job shall be a suspended
	      job. If there are at least two suspended jobs, then the previous job also shall be a suspended job.

       <job-number>
	      A number that can be used to identify the process group to the wait, fg, bg, and kill utilities. Using these utilities, the job  can
	      be identified by prefixing the job number with '%' .

       <state>
	      One of the following strings (in the POSIX locale):

       Running
	      Indicates that the job has not been suspended by a signal and has not exited.

       Done
	      Indicates that the job completed and returned exit status zero.

       Done(code)
	      Indicates  that  the job completed normally and that it exited with the specified non-zero exit status, code, expressed as a decimal
	      number.

       Stopped
	      Indicates that the job was suspended by the SIGTSTP signal.

       Stopped (SIGTSTP)

	      Indicates that the job was suspended by the SIGTSTP signal.

       Stopped (SIGSTOP)

	      Indicates that the job was suspended by the SIGSTOP signal.

       Stopped (SIGTTIN)

	      Indicates that the job was suspended by the SIGTTIN signal.

       Stopped (SIGTTOU)

	      Indicates that the job was suspended by the SIGTTOU signal.

       The implementation may substitute the string Suspended in place of Stopped. If the job was terminated by a signal, the format of <state> is
       unspecified,  but  it shall be visibly distinct from all of the other <state> formats shown here and shall indicate the name or description
       of the signal causing the termination.

       <command>
	      The associated command that was given to the shell.

       If the -l option is specified, a field containing the process group ID shall be inserted before the <state> field. Also, more processes	in
       a process group may be output on separate lines, using only the process ID and <command> fields.

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  -p	option is the only portable way to find out the process group of a job because different implementations have different strategies
       for defining the process group of the job. Usage such as $( jobs -p) provides a way of referring to the process group  of  the  job  in	an
       implementation-independent way.

       The  jobs  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, jobs is generally implemented as a shell regular
       built-in.

EXAMPLES

       None.

RATIONALE

       Both  "%%"  and "%+" are used to refer to the current job.  Both forms are of equal validity-the "%%" mirroring "$$" and "%+" mirroring the
       output of jobs.	Both forms reflect historical practice of the KornShell and the C shell with job control.

       The job control features provided by bg, fg, and jobs are 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).

       The  jobs  utility  is not dependent on the job control option, as are the seemingly related bg and fg utilities because jobs is useful for
       examining background jobs, regardless of the condition of job control.  When the user has invoked a set +m command and job control has been
       turned  off,  jobs can still be used to examine the background jobs associated with that current session.  Similarly, kill can then be used
       to kill background jobs with kill% <background job number>.

       The output for terminated jobs is left unspecified to accommodate various historical systems. The following formats have been witnessed:

	1. Killed( signal name)

	2. signal name

	3. signal name( coredump)

	4. signal description- core dumped

       Most users should be able to understand these formats, although it means that applications have trouble parsing them.

       The calculation of job IDs was not described since this would suggest an implementation, which may impose unnecessary restrictions.

       In an early proposal, a -n option was included to "Display the status of jobs that have changed, exited, or stopped since the  last  status
       report". It was removed because the shell always writes any changed status of jobs before each prompt.

FUTURE DIRECTIONS

       None.

SEE ALSO

       Shell Execution Environment, bg, fg, kill(), wait()

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- 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								  JOBS(1P)