Which shell command is used to continue background execution of a suspended command?
A
&
B
bg
Correta
C
cont
D
exec
E
:&
Explicação Oficial / Explicações da Comunidade
The bg command is used to resume a suspended job and run it in the background. When a command is suspended (e.g., by pressing Ctrl+Z), it is stopped and placed into a suspended state. The bg command takes that suspended job and continues its execution in the background, allowing the shell to accept new commands immediately.
How it Works
Suspending a job: Pressing Ctrl+Z sends SIGTSTP to the foreground process, stopping it. The shell then reports the job number and its state (suspended).
Using bg: Typing bg (optionally with a job ID like %1) resumes the job in the background. The shell sends SIGCONT to the process group, and the job continues running but does not have control of the terminal.
The & operator is used to start a command directly in the background, not to resume a suspended one.
cont is not a standard shell command; it is a misspelling of continue in some contexts but not for job control.
exec replaces the current shell with a new command; it does not resume background jobs.
:& is not a valid shell command; : is a null command, and appending & would attempt to run it in the background, but it does not resume a suspended job.
