bg - Runs jobs in the background
The C shell has a built-in version of the bg command. If you are using the C shell, and want to guarantee that you are using the command described here, you must specify the full path /usr/bin/bg. See the csh(1) reference page for a description of the built-in command.
Interfaces documented on this reference page conform to industry standards as follows:
bg: XPG4, XPG4-UNIX
Refer to the
reference page for more information
about industry standards and associated tags.
Specifies the job to be resumed as a background job. If no
operand is given, the most recently suspended job is
used. The format of
is described in the
section of the
If job control is enabled (see the description of set -m in the ksh(1) reference page), the bg utility resumes suspended jobs from the current environment by running them as background jobs. If the job specified by job_id is a job already running in the background, the bg utility has no effect and will exit successfully.
to place a job into the background causes
its process ID to become ``known in the current shell execution environment'',
as if it had been started as an asynchronous list. See the
section of the
If job control is disabled, the
exits with an error and no job is placed in the background.
utility does not work as expected
when it is operating in its own utility execution environment because that
environment has no suspended jobs.
The following exit values are returned:
An error occurred.
The following environment variables affect the execution of
Provides a default value for the internationalization
variables that are unset or null. If
is unset or null, the corresponding value from the default locale is used.
If any of the internationalization variables contain an invalid setting, the
utility behaves as if none of the variables had been defined.
If set to a non-empty string value, overrides
the values of all the other internationalization variables.
Determines the locale for the interpretation
of sequences of bytes of text data as characters (for example, single-byte
as opposed to multibyte characters in arguments).
Determines the locale used to affect the
format and contents of diagnostic messages written to standard error.
Determines the location of message catalogues
for the processing of
Commands: csh(1), fg(1), jobs(1), kill(1), ksh(1), Bourne shell sh(1b), POSIX shell sh(1p), wait(1)