cissp certified information systems security professional study guide pdf

its address, and the collection of all possible addresses is called the virtual address space.2.how the compiler and runtime systems divide the memory space into more manageable units to hold different program objects (program object), that is, procedural data, directives, and control information. the value of a pointer in C (whether it is pointing to an integer, a struct, or some other program object) is

document descriptor and stream buffer. To reduce system overhead.10.9 synthesis: What should be used I/O functionMost of the time, you can use standard I/O.Use the Rio function when using a network socket. You need to format the output, use the sprintf function to format a string, and then use Rio_writen to send it to the socket interface. Format the input, use Rio_readlineb to read a complete line of text, and then use scanf to extract the different fields from the line of text.Summary:The con

, double Int→float will not overflow but may be roundedInt/float→double results retain exact valuesDouble→float may overflow to ±∞ and may be rounded due to small accuracyThe float/double→int rounds to 0 and can overflow.Problems encountered:1. Error in compiling the 28-page code in the bookCheck the code seems to be nothing wrong, do not know why ... at last, I commented out the line . The source code is as follows2. Exercise 2.52 do not understand, I hope the teacher can explain in classI

where the contents of the disk sector should be stored. The logical block number translates a sector address and then transfers the content to main memory without CPU interference, a process known as direct memory access. This data transfer is called DMA transfer. When the volume of a disk sector is securely stored in main memory, the disk controller notifies the CPU by sending an interrupt signal to the CPU. Problem:may be a bit low-level, the book says that the main me

autowrite(aw) set AutoArchive, default not open Enter or in command line :set background=dark mode light , set the background style Command line mode input :set backup(bk) set automatic backup, default not open Command line mode input : set cindent(cin) set C language style indent 3.Linux System Programming(1) Use of GCCcompiler use of GCC Second, the problems encountered and sentiment:Early groping vim time with too much, followed the tutorial done two times, think some instru

expressed in the desired floating-point form.1. Rounding to even numbersRounds a number up or down so that the lowest effective number of the result is even.2. Rounding to 03. Rounding up4. Rounding Down34 you can see the upper bound.Rounding to even gets the closest match.4. Floating-point arithmeticFloating-point addition: exchangeable, non-associative, satisfying monotonicityFloating-point multiplication: exchangeable, non-associative, non-assignable, satisfies the following monotonicityFloa

frees the allocated blocks that the program no longer needs, called garbage , and the process of automatically reclaiming heap storage is called garbage collection . The garbage collector periodically identifies the garbage blocks and calls free accordingly, putting the blocks back into the idle listSecond, the garbage collector sees the memory as a forward-reaching graph, only when there is a path from any root node to reach p, it is said that node p is reachable, and the unreachable point is

. Garbage collectionvoid Garbage (){int *p = (int *) Malloc (15213)Return}garbage collector:is a dynamic storage allocator that automatically frees allocated blocks that are no longer needed by the program. These blocks are called garbage. The process of automatically reclaiming heap storage is called garbage collection. The following functions are used in the description of Marksweep: where PTR is defined as typedef void *PTRPtrisptr (PTR p): if p points to a word in an allocated block, it ret

-feeling bad, read a lot of confusion, code execution is also less. This week's code package gives me a good chance to practice understanding! So I just took the code out of the video in handy. The feeling learned a lot of content. In particular, the function of fork such functions are in the execution of the code to feel its principle. It was really touching when I finished it!!!Because there is also a recent project of this course, the internet also searched a lot of communication between the

function, which can be seen as a buffer version of the UNIX read function. When calling Rio_read requires reading n bytes, there are rp->rio_cnt unread bytes in the read buffer. If the buffer is empty, the read system function is called to fill the buffer. This read call is not an error if it receives an insufficient value, except that the read buffer is partially populated. Once the buffer is non-empty, Rio_read copies N and rp->rio_cnt from the read buffer to the user buffer, and returns the

("fork");else if (Newpid = = 0)Child_code (DELAY);ElseParent_code (NEWPID);}Operation diagram:Shows that the wait function tells the parent process that the child process is the same as and ends with the arguments passed to the wait. When the parent process calls wait, an integer variable address is passed to the function, and the kernel saves the child process's exit state in the variable.V. Problems encountered and Solutions1. Virtual machine can not run, a virtual machine computer on the car