system
Built-in commands are not strictly necessary. However, if is a commonly used command you will get a performance benefit from having the shell execute it directly rather than doing a file system search to find the program to execute the command.
the command is not available it is used in windows.its means at time execute command
apachectl start
your questions makes zero sense
You can right-click on an appropriate object to select a command, then right-click to execute the command. You can click on an icon to execute some commands.
enter
Types of System CallsThe main types of system calls are as follows:Process Control: These types of system calls are used to control the processes. Some examples are end, abort, load, execute, create process, terminate process etc.File Management: These types of system calls are used to manage files. Some examples are Create file, delete file, open, close, read, write etc.Device Management: These types of system calls are used to manage devices. Some examples are Request device, release device, read, write, get device attributes etc.Information Maintenance: These types of system calls are used to set system data and get process information. Some examples are time, OS parameters, id, time used etc.Communications: These types of system calls are used to establish a connection. Some examples are send message, received messages, terminate etc
Command prompt/line is used to execute entered commands. Command prompt is mostly commonly used to execute batch files, perform advanced administrative functions, and troubleshoot and solve certain kinds of windows issues.
Incident Command System is a widely used and accepted tool for command, control, and coordination of a disaster response.
The fork system call is used to create new child process which followed his parent process
You can schedule jobs using cron and the /etc/crontab file, or you can use the "at" command
Incident Command System