Search results
Results From The WOW.Com Content Network
File descriptors for a single process, file table and inode table. Note that multiple file descriptors can refer to the same file table entry (e.g., as a result of the dup system call [3]: 104 ) and that multiple file table entries can in turn refer to the same inode (if it has been opened multiple times; the table is still simplified because it represents inodes by file names, even though an ...
Zombie process. On Unix and Unix-like computer operating systems, a zombie process or defunct process is a process that has completed execution (via the exit system call) but still has an entry in the process table: it is a process in the "terminated state". This occurs for the child processes, where the entry is still needed to allow the ...
A process control block ( PCB ), also sometimes called a process descriptor, is a data structure used by a computer operating system to store all the information about a process . When a process is created (initialized or installed), the operating system creates a corresponding process control block, which specifies and tracks the process state ...
A page table is a data structure used by a virtual memory system in a computer to store mappings between virtual addresses and physical addresses. Virtual addresses are used by the program executed by the accessing process, while physical addresses are used by the hardware, or more specifically, by the random-access memory (RAM) subsystem.
cron. The cron command-line utility is a job scheduler on Unix-like operating systems. Users who set up and maintain software environments use cron to schedule jobs [ 1] (commands or shell scripts ), also known as cron jobs, [ 2][ 3] to run periodically at fixed times, dates, or intervals. [ 4]
When a child process terminates, it becomes a zombie process, and continues to exist as an entry in the system process table even though it is no longer an actively executing program. Under normal operation it will typically be immediately waited on by its parent, and then reaped by the system, reclaiming the resource (the process table entry).
A process moves into the running state when it is chosen for execution. The process's instructions are executed by one of the CPUs (or cores) of the system. There is at most one running process per CPU or core. A process can run in either of the two modes, namely kernel mode or user mode. [ 1][ 2]
fork() is the name of the system call that the parent process uses to "divide" itself ("fork") into two identical processes. After calling fork(), the created child process is an exact copy of the parent except for the return value of the fork () call. This includes open files, register state, and all memory allocations, which includes the ...