bg [jobspec …]
Resume each suspended job jobspec in the background, as if it had been started with ‘&’. If jobspec is not supplied, the current job is used. The return status is zero unless it is run when job control is not enabled, or, when run with job control enabled, any jobspec was not found or specifies a job that was started without job control.
Resume the job jobspec in the foreground and make it the current job. If jobspec is not supplied, the current job is used. The return status is that of the command placed into the foreground, or non-zero if run when job control is disabled or, when run with job control enabled, jobspec does not specify a valid job or jobspec specifies a job that was started without job control.
jobs [-lnprs] [jobspec] jobs -x command [arguments]
The first form lists the active jobs. The options have the following meanings:
List process IDs in addition to the normal information.
Display information only about jobs that have changed status since the user was last notified of their status.
List only the process ID of the job’s process group leader.
Display only running jobs.
Display only stopped jobs.
If jobspec is given, output is restricted to information about that job. If jobspec is not supplied, the status of all jobs is listed.
If the -x option is supplied,
jobs replaces any
jobspec found in command or arguments with the
corresponding process group ID, and executes command,
passing it arguments, returning its exit status.
kill [-s sigspec] [-n signum] [-sigspec] jobspec or pid kill -l|-L [exit_status]
Send a signal specified by sigspec or signum to the process
named by job specification jobspec or process ID pid.
sigspec is either a case-insensitive signal name such as
SIGINT (with or without the
or a signal number; signum is a signal number.
If sigspec and signum are not present,
SIGTERM is used.
The -l option lists the signal names.
If any arguments are supplied when -l is given, the names of the
signals corresponding to the arguments are listed, and the return status
exit_status is a number specifying a signal number or the exit
status of a process terminated by a signal.
The -L option is equivalent to -l.
The return status is zero if at least one signal was successfully sent,
or non-zero if an error occurs or an invalid option is encountered.
wait [-fn] [-p varname] [jobspec or pid …]
Wait until the child process specified by each process ID pid
or job specification jobspec exits and return the exit status of the
last command waited for.
If a job spec is given, all processes in the job are waited for.
If no arguments are given,
wait waits for all running background jobs and
the last-executed process substitution, if its process id is the same as
and the return status is zero.
If the -n option is supplied,
wait waits for a single job
from the list of pids or jobspecs or, if no arguments are
supplied, any job,
to complete and returns its exit status.
If none of the supplied arguments is a child of the shell, or if no arguments
are supplied and the shell has no unwaited-for children, the exit status
If the -p option is supplied, the process or job identifier of the job
for which the exit status is returned is assigned to the variable
varname named by the option argument.
The variable will be unset initially, before any assignment.
This is useful only when the -n option is supplied.
Supplying the -f option, when job control is enabled,
wait to wait for each pid or jobspec to
terminate before returning its status, intead of returning when it changes
If neither jobspec nor pid specifies an active child process
of the shell, the return status is 127.
disown [-ar] [-h] [jobspec … | pid … ]
Without options, remove each jobspec from the table of
If the -h option is given, the job is not removed from the table,
but is marked so that
SIGHUP is not sent to the job if the shell
If jobspec is not present, and neither the -a nor the
-r option is supplied, the current job is used.
If no jobspec is supplied, the -a option means to remove or
mark all jobs; the -r option without a jobspec
argument restricts operation to running jobs.
Suspend the execution of this shell until it receives a
A login shell cannot be suspended; the -f
option can be used to override this and force the suspension.
When job control is not active, the
builtins do not accept jobspec arguments. They must be
supplied process IDs.