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PROLOG

       This  manual  page  is part of the POSIX Programmer's Manual.  The Linux implementation of
       this interface may differ (consult the corresponding 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 Section 2.12, 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 Section
       2.9.3.1, Examples.

OPTIONS

       The jobs utility shall conform to the Base Definitions  volume  of  POSIX.1‐2017,  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  displayed.  The  format  of
                 job_id  is  described  in  the  Base Definitions volume of POSIX.1‐2017, Section
                 3.204, 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  POSIX.1‐2017,  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\n", <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\n", <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 POSIX.1‐2017 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.

COPYRIGHT

       Portions of this text are reprinted and  reproduced  in  electronic  form  from  IEEE  Std
       1003.1-2017,  Standard  for  Information Technology -- Portable Operating System Interface
       (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C)  2018  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 .

       Any typographical or formatting errors that appear in this page are most  likely  to  have
       been  introduced  during  the conversion of the source files to man page format. To report
       such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .