What are foreground and background processes in LINUX/UNIX? How do you run shell commands as foreground and background processes? Give an example for each.
What will be an ideal response?
A process whose standard input is attached to the keyboard is called a foreground process. While this process executes, you don’t get the shell prompt and, therefore, cannot run another command. A process that returns the shell prompt before it starts running is called a background process. You must terminate a command by an ampersand (&) in order to run it in the background. When a process runs in the background, it executes at a lower priority.
In the following session, the ls -l command is executed in the foreground and the find command is executed in the background. Note that the system displays the processs and job IDs for the background process before returning the shell prompt. The number in brackets (1) is the job ID and the second number (23985) is the process ID.
```
$ ls -l
[ output of the ls -l command ]
$ find / -name foo -print > foo.paths 2> /dev/null &
[ 1 ] 23985
$
```
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Indicate whether the statement is true or false
What happens when a dialog box is closed using the Close button?
A) All changes made in the dialog box are applied. B) Only changes made in the dialog box are applied. C) All change that is made must be less than 20 dollars. D) All changes made in the dialog box are not applied.
First normal form refers to ____.
A. redundant data in an original table that is extracted, placed in a new table, and related to the first table B. derived fields that are removed C. a 2-dimensional table with rows and columns D. calculated fields that are removed