Computer disk partitioning standard for legacy Macintosh computers
Apple Partition Map (APM) is a partition scheme used to define the low-level organization of data on disks formatted for use with 68k and PowerPC Macintosh computers. It was introduced with the Macintosh II.[1]
Disks using the Apple Partition Map are divided into logical blocks, with 512 bytes usually belonging to each block. The first block, Block 0, contains an Apple-specific data structure called "Driver Descriptor Map" for the Macintosh Toolbox ROM to load driver updates and patches before loading from a MFS or HFS partition.[2] Because APM allows 32 bits worth of logical blocks, the historical size of an APM formatted disk using small blocks[3] is limited to 2 TiB.[4]
The Apple Partition Map maps out all space used (including the map) and unused (free space) on disk, unlike the minimal x86 master boot record that only accounts for used non-map partitions. This means that every block on the disk (with the exception of the first block, Block 0) belongs to a partition.
Some hybrid disks contain both an ISO 9660 primary volume descriptor and an Apple Partition Map, thus allowing the disc to work on different types of computers, including Apple systems.
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and 27 Related for: Apple Partition Map information
ApplePartitionMap (APM) is a partition scheme used to define the low-level organization of data on disks formatted for use with 68k and PowerPC Macintosh...
as the name implies is a unique id for each partition. Advanced Active Partition (AAP) ApplePartitionMap (APM) Boot Engineering Extension Record (BEER)...
other formats that divide a disk drive into partitions, such as: GUID Partition Table (GPT), Applepartitionmap (APM), or BSD disklabel. This section describes...
non-partitioned and partitioned media. In particular, it recognizes the GUID Partition Table (GPT), Applepartitionmap, PC/Intel BIOS partition tables...
or changing partition table between ApplePartitionMap, GUID Partition Table, and master boot record (MBR) Restoring volumes from Apple Software Restore...
in order to write data safely onto an HFS+ partition. Provided the partition isn't being used by Apple's Time Machine software, journaling can be disabled...
Management, a legacy technology in personal computers ApplePartitionMap, computer disk partition scheme Application performance management, a discipline...
the partition contains or to flag special access methods used to access these partitions (e.g. special CHS mappings, LBA access, logical mapped geometries...
optimal method. ReiserFS v3 images should not be stored on a ReiserFS v3 partition (e.g. backups or disk images for emulators) without transforming them...
Comparison of file systems List of partition IDs (MBR) Master Boot Record (MBR) GUID Partition Table (GPT) ApplePartitionMap Amiga Rigid Disk Block Timeline...
If present, an Applepartitionmap begins 512 bytes into the disc; if there is no partitionmap, the header for an Apple HFS partition (known as a Master...
system solved the two major problems in the Minix file system (maximum partition size and filename length limitation to 14 characters), and allowed 2 gigabytes...
VxFS) Versity VSM (SAM-QFS ported to Linux), ScoutFS VMware VMFS WekaFS Apple Xsan DragonFly BSD HAMMER2 Distributed file systems do not share block level...
used to access specific unique resources on those devices, such as disk partitions. Additionally, device files are useful for accessing system resources...
work as NAND devices have a sequential I/O interface and cannot be memory-mapped for reading. Hard links. This was not possible in JFFS because of limitations...
2004; 20 years ago (2004) with Linux Partition IDs Apple_UNIX_SVR2 (ApplePartitionMap) 0x83 (MBR) Basic data partition (GPT) Structures Directory contents...
entire partition is randomized - encrypted files strongly resemble randomized sections of the partition, and so when files are stored on the partition, there...
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