The term magic number or magic constant refers to the anti-pattern of using numbers directly in source code. This has been referred to as breaking one of the oldest rules of programming, dating back to the COBOL, FORTRAN and PL/1 manuals of the 1960s.[1] The use of unnamed magic numbers in code obscures the developers' intent in choosing that number,[2] increases opportunities for subtle errors (e.g. is every digit correct in 3.14159265358979323846 and is this equal to 3.14159?) and makes it more difficult for the program to be adapted and extended in the future.[3] Replacing all significant magic numbers with named constants (also called explanatory variables) makes programs easier to read, understand and maintain.[4]
Partition Magic 8 0 serial number 52
The problems associated with magic 'numbers' described above are not limited to numerical types and the term is also applied to other data types where declaring a named constant would be more flexible and communicative.[1] Thus, declaring const string testUserName = "John" is better than several occurrences of the 'magic value' "John" in a test suite.
where a is an array object, the function randomInt(x) chooses a random integer between 1 and x, inclusive, and swapEntries(i, j) swaps the ith and jth entries in the array. In the preceding example, 52 is a magic number. It is considered better programming style to write the following:
Since the Sixth and Seventh Editions of Unix employed paging code, the dual role of the header constant was hidden. That is, the exec() service read the executable file header (meta) data into a kernel space buffer, but read the executable image into user space, thereby not using the constant's branching feature. Magic number creation was implemented in the Unix linker and loader and magic number branching was probably still used in the suite of stand-alone diagnostic programs that came with the Sixth and Seventh Editions. Thus, the header constant did provide an illusion and met the criteria for magic.
In Version Seven Unix, the header constant was not tested directly, but assigned to a variable labeled ux_mag[9] and subsequently referred to as the magic number. Probably because of its uniqueness, the term magic number came to mean executable format type, then expanded to mean file system type, and expanded again to mean any type of file.
The Unix utility program file can read and interpret magic numbers from files, and the file which is used to parse the information is called magic. The Windows utility TrID has a similar purpose.
Used by VLC player and some IP cameras in RTP/RTCP protocol, VLC player sends four bytes in the order of the endianness of the system. Some IP cameras expect the player to send this magic number and do not start the stream if it is not received.
The match keys introduced so far only provide limited matching capabilities. Realistically we require much finer control: we want to identify devices based on advanced properties such as vendor codes, exact product numbers, serial numbers, storage capacities, number of partitions, etc.
The Linux kernel actually represents devices in a tree-like structure, and this information is exposed through sysfs and useful when writing rules. For example, the device representation of my hard disk device is a child of the SCSI disk device, which is in turn a child of the Serial ATA controller device, which is in turn a child of the PCI bus device. It is likely that you will find yourself needing to refer to information from a parent of the device in question, for example the serial number of my hard disk device is not exposed at the device level, it is exposed by its direct parent at the SCSI disk level.
The most common operators are %k and %n. %k evaluates to the kernel name for the device, e.g. "sda3" for a device that would (by default) appear at /dev/sda3. %n evaluates to the kernel number for the device (the partition number for storage devices), e.g. "3" for /dev/sda3.
From the Windows NT-based (Windows XP and 7 specifically) command prompt, how can I get the serial number of a hard drive as a variable? The one I'm looking at is the serial number of the physical hard disk drive
I have a script I use to backup data using robocopy. Because it stores critical/sensitive data, I prefer to hide the partition rather than allowing Windows to mount it automatically, and only use the script to unhide the partition, backup the date with robocopy, and hide the partition again. I use the HDD/SSD serial number in order to mount the drive and run the script.
Recommended Programming ProcedureThe following is a step-by-step procedure recommended for programming your VISTA-50P/VISTA-50PUL system. 1. Set the keypads (and other peripheral devices) to the appropriate addresses. 2. Set factory defaults by pressing ,97. This will automatically enable keypad addresses 00-03, so be sure at least one keypad is set to one of these addresses. 3. Program system-wide (global) data fields. Using the programming form as a guide, enter program mode and program all system-wide programming fields. These options affect the entire system, regardless of partitions. They include control options, downloader and dialer options, RF options, event logging options, etc. Refer to the Program Field Index for a listing of the program fields and their function. Note that field 2,00 (number of partitions) must be programmed before continuing. 4. Program partition-specific fields. When the system-wide fields have been programmed, program all partition-specific programming fields by first pressing ,91 to select a partition (while still in data field program mode). Then enter the first partitionspecific field number ,09. When you are finished, the next partition-specific field is automatically displayed. Partition-specific fields can have different values for each partition. To program the fields for the next partition, press ,91, enter the desired partition number, then enter field ,09. Refer to the PROGRAMMING section in the VISTA-50P/VISTA-50PUL Installation and Setup Guide for detailed instructions. 5. Use #93 Menu Mode for device programming. Refer to Device Programming in this guide to assign keypad ID numbers and default partitions for each keypad, and to selectively suppress certain keypad sounding options. Also use this mode to assign RF receivers, relay modules, and the VIP module. 6. Use #93 Menu Mode for zone programming. Refer to Zone Programming in this guide to program zone response types, assign right loop zones and wireless zones, assign zones to partitions, and to program alarm report codes. 7. Use #93 Menu Mode for programming outputs. Refer to Output Programming in this guide to program desired output operation. 8. Program Communication options. Refer to System Communication section in the VISTA-50P/VISTA-50PUL Installation and Setup Guide for detailed instructions. Then use #93 menu mode to program report codes. 9. Use #93 Menu Mode for programming alpha descriptors. Refer to Alpha Programming in this guide to enter zone and partition descriptors and a custom installer's message. 10. Use #93 Menu Mode for relay voice descriptors and custom word substitutes. Refer to Relay Voice Descriptors in this guide for further instructions for programming relay descriptors to be annunciated by the VIP module, as well as the Custom Index section for custom word substitutes. 11. Use #80 Mode for programming schedules. Refer to the Scheduling Menu Prompts in the VISTA-50P/VISTA-50PUL Installation and Setup Guide to program open/close schedules, temporary and holiday schedules, limitation of access schedules, and timedriven events. 12. Define user access codes. Refer to User Access Codes in the VISTA-50P/VISTA-50PUL Installation and Setup Guide to program authority level, O/C reporting option, partition assignments, and RF key assignments for each user. 13. Exit Programming Mode. Exit programming mode by pressing either ,98 or ,99. Additional entries of ,99 are required if the exit is being done from fields 1,00 and above. To prevent re-access to programming mode using the Installer's code, use ,98. The only way to re-access programming mode is by depressing both the [,] and [#] keys at the same time within 30 seconds of powerup. Exiting by using ,99 always allows reentry into programming mode using the Installer code. Either way of exiting allows access via downloading. Note that if local programming lockout is set via downloading, programming mode cannot be entered at the keypad.
Partition-Specific Fields(Duplicate this page for each partition in the installation.) To program these fields, 1. Press *91 to select a partition. 2. Enter a partition-specific field number (ex. *09). 3. Make the required entry. 4. Repeat steps 1-3 for each partition in the system. PARTITION #____ PROGRAM FIELDS1st Page Fields
Zone ProgrammingIf using 5800 Series transmitters, do not the install batteries until you are ready to enroll them. After enrolling the transmitter, the battery need not be removed. This is to prevent enrolling the wrong serial number.
After you have enrolled each wireless device, remove ONE of the serial number labels from that device and affix it in the appropriate column on the worksheets provided later in this Programming Guide; then enter the other information (zone number, zone type, etc.) relevant to that device. When you have finished programming all zones, test each using the system's Test Mode. Do not use the Transmitter ID Sniffer Mode. The system checks only for transmission of one zone on a particular transmitter, NOT the zones assigned to each additional loop, and also does not verify polling loop type zones.
After you have enrolled each wireless device, remove ONE of the serial number labels from that device and affix it in the appropriate column on the worksheets provided later in this Programming Guide; then enter the other information (zone number, zone type, etc.) relevant to that device. 2ff7e9595c
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