Revisions to Difference between nohup, disown and &

added other condition when the shell stops waiting for the shell, from comment by Max

edited Jun 21, 2020 at 6:16

The process running foo is created.
The process inherits stdin, stdout, and stderr from the shell. Therefore it is also connected to the same terminal.
If the shell receives a SIGHUP, it also sends a SIGHUP to the process (which normally causes the process to terminate).
Otherwise the shell waits (is blocked) until the process terminates or gets stopped.

The process running foo is created.
The process inherits stdin, stdout, and stderr from the shell. Therefore it is also connected to the same terminal.
If the shell receives a SIGHUP, it also sends a SIGHUP to the process (which normally causes the process to terminate).
Otherwise the shell waits (is blocked) until the process terminates.

The process running foo is created.
The process inherits stdin, stdout, and stderr from the shell. Therefore it is also connected to the same terminal.
If the shell receives a SIGHUP, it also sends a SIGHUP to the process (which normally causes the process to terminate).
Otherwise the shell waits (is blocked) until the process terminates or gets stopped.

corrected single word mistake

& puts the job in the background, that is, makes it block on attempting to read input, and makes the shell not wait for its completion.
disown removes the process from the shell's job control, but it still leaves it connected to the terminal. One of the results is that the shell won't send it a SIGHUP. Obviously, it can only be applied to background jobs, because you cannot enter it when a foreground job is running.
nohup disconnects the process from the terminal, redirects its output to nohup.out and shields it from SIGHUP. One of the effects (the naming one) is that the process won't receive any sent NOHUPSIGHUP. It is completely independent from job control and could in principle be used also for foreground jobs (although that's not very useful).

& puts the job in the background, that is, makes it block on attempting to read input, and makes the shell not wait for its completion.
disown removes the process from the shell's job control, but it still leaves it connected to the terminal. One of the results is that the shell won't send it a SIGHUP. Obviously, it can only be applied to background jobs, because you cannot enter it when a foreground job is running.
nohup disconnects the process from the terminal, redirects its output to nohup.out and shields it from SIGHUP. One of the effects (the naming one) is that the process won't receive any sent NOHUP. It is completely independent from job control and could in principle be used also for foreground jobs (although that's not very useful).

& puts the job in the background, that is, makes it block on attempting to read input, and makes the shell not wait for its completion.
disown removes the process from the shell's job control, but it still leaves it connected to the terminal. One of the results is that the shell won't send it a SIGHUP. Obviously, it can only be applied to background jobs, because you cannot enter it when a foreground job is running.
nohup disconnects the process from the terminal, redirects its output to nohup.out and shields it from SIGHUP. One of the effects (the naming one) is that the process won't receive any sent SIGHUP. It is completely independent from job control and could in principle be used also for foreground jobs (although that's not very useful).

Minor grammar tweak/correction.

It closes standard input (the program will not be able to read any input, even if it is run in the foreground. it is not halted, but will receive andan error code or EOF).
It redirects standard output and standard error to the file nohup.out, so the program won't fail for writing to standard output if the terminal fails, andso whatever the process writes is not lost.
It prevents the process from receiving a SIGHUP (thus the name).

It closes standard input (the program will not be able to read any input, even if it is run in the foreground. it is not halted, but will receive and error code or EOF).
It redirects standard output and standard error to the file nohup.out, so the program won't fail for writing to standard output if the terminal fails, and whatever the process writes is not lost.
It prevents the process from receiving a SIGHUP (thus the name).

It closes standard input (the program will not be able to read any input, even if it is run in the foreground. it is not halted, but will receive an error code or EOF).
It redirects standard output and standard error to the file nohup.out, so the program won't fail for writing to standard output if the terminal fails, so whatever the process writes is not lost.
It prevents the process from receiving a SIGHUP (thus the name).