hệ điều hành nguyễn văn hiệp chương ter 10 unix and linux sinhvienzone com

Chapter 10 Case Study 1: UNIX and LINUX 10.1 History of unix 10.2 Overview of unix 10.3 Processes in unix 10.4 Memory management in unix 10.5 Input/output in unix 10.6 The unix file system 10.7 Security in unix SinhVienZone.com https://fb.com/sinhvienzonevn UNIX User Interface The layers of a UNIX system SinhVienZone.com https://fb.com/sinhvienzonevn UNIX Utility Programs A few of the more common UNIX utility programs required by POSIX SinhVienZone.com https://fb.com/sinhvienzonevn UNIX Kernel Approximate structure of generic UNIX kernel SinhVienZone.com https://fb.com/sinhvienzonevn Processes in UNIX Process creation in UNIX SinhVienZone.com https://fb.com/sinhvienzonevn POSIX The signals required by POSIX SinhVienZone.com https://fb.com/sinhvienzonevn System Calls for Process Management s is an error code pid is a process ID residual is the remaining time from the previous alarm SinhVienZone.com https://fb.com/sinhvienzonevn POSIX Shell A highly simplified shell SinhVienZone.com https://fb.com/sinhvienzonevn Threads in POSIX The principal POSIX thread calls SinhVienZone.com https://fb.com/sinhvienzonevn The ls Command Steps in executing the command ls type to the shell SinhVienZone.com https://fb.com/sinhvienzonevn 10 The UNIX File System (2) • Before linking • After linking (a) Before linking (b) After linking SinhVienZone.com https://fb.com/sinhvienzonevn 26 The UNIX File System (3) • Separate file systems • After mounting (a) (b) (a) Before mounting (b) After mounting SinhVienZone.com https://fb.com/sinhvienzonevn 27 Locking Files (a) File with one lock (b) Addition of a second lock (c) A third lock SinhVienZone.com https://fb.com/sinhvienzonevn 28 System Calls for File Management • s is an error code • fd is a file descriptor • position is a file offset SinhVienZone.com https://fb.com/sinhvienzonevn 29 The lstat System Call Fields returned by the lstat system call SinhVienZone.com https://fb.com/sinhvienzonevn 30 System Calls for Directory Management • s is an error code • dir identifies a directory stream • dirent is a directory entry SinhVienZone.com https://fb.com/sinhvienzonevn 31 UNIX File System (1) Disk layout in classical UNIX systems SinhVienZone.com https://fb.com/sinhvienzonevn 32 UNIX File System (2) Directory entry fields Structure of the i-node SinhVienZone.com https://fb.com/sinhvienzonevn 33 UNIX File System (3) The relation between the file descriptor table, the open file description SinhVienZone.com https://fb.com/sinhvienzonevn 34 UNIX File System (4) • A BSD directory with three files • The same directory after the file voluminous has been removed SinhVienZone.com https://fb.com/sinhvienzonevn 35 The Linux File System Layout of the Linux Ex2 file system SinhVienZone.com https://fb.com/sinhvienzonevn 36 Network File System (1) • Examples of remote mounted file systems • Directories are shown as squares, files as circles SinhVienZone.com https://fb.com/sinhvienzonevn 37 Network File System (2) The NFS layer structure The NFS layer structure SinhVienZone.com https://fb.com/sinhvienzonevn 38 Security in UNIX Some examples of file protection modes SinhVienZone.com https://fb.com/sinhvienzonevn 39 System Calls for File Protection • s is an error code • uid and gid are the UID and GID, respectively SinhVienZone.com https://fb.com/sinhvienzonevn 40 ... calls SinhVienZone. com https://fb .com/ sinhvienzonevn The ls Command Steps in executing the command ls type to the shell SinhVienZone. com https://fb .com/ sinhvienzonevn 10 Flags for Linux clone Bits... SinhVienZone. com https://fb .com/ sinhvienzonevn UNIX Kernel Approximate structure of generic UNIX kernel SinhVienZone. com https://fb .com/ sinhvienzonevn Processes in UNIX Process creation in UNIX SinhVienZone. com. . .UNIX User Interface The layers of a UNIX system SinhVienZone. com https://fb .com/ sinhvienzonevn UNIX Utility Programs A few of the more common UNIX utility programs required by POSIX SinhVienZone. com