DRIVEINFO(8) BSD System Manager’s Manual DRIVEINFO(8)

NAME

driveinfo — provide partition information for GPT drives

SYNOPSIS

driveinfo [−A] [−R options-to-reset] [−a byte-alignment] [−b] [−c column-list] [−defhimprs] [−t maximum-entries] [−vx] [−z file-list] [−−] [device]

DESCRIPTION

The driveinfo command gets detailed information about a specific drive. The script parses property lists emitted by the diskutil(8) command to compile the information. If the drive contains a GUID Partition Table (GPT), then detailed information about each partition is also included in a tabular form. This also allows free space on a drive, using a GPT, to be identified.

The gpt(8) command can be used to view the actual stored GPT values in in a tabular form. Starting with macOS, the gpt(8) command can no longer read the GPT on an operating system boot drive, unless System Integrity Protection (SIP) is disabled. The driveinfo command does not require disabling SIP and can produce the same basic tabular output as the gpt(8) command.

The options are applied as read from left to right and are as follows:

−A

Reset to the default all options. This option is the same as entering the −R abcdefimrstx option.

−R options-to-reset

Reset to the default value any options given as the argument.

−a byte-alignment

Set the byte alignment value used to determine if the "A" and "S" error codes should be issued. The default is to never issue either code. Normally, the byte alignment value should be a power of 2 greater than the logical sector size.

−b

Display blocks instead of bytes. Each block is equal to the logical sector size in bytes.

−c column-list

Specify which columns to display. Each character in the argument represents a column type. The list of possible column types is given in the COLUMNS section. The default is to display the "cstimn" column types.

−d

Omit the header.

−e

Omit the table.

−f

Force use of color. Color sequences are normally disabled if the output is not directed to a terminal. This can be overridden by setting this flag.

−h

Display this man page with overstriking suppressed, then quit. All previous options are ignored.

−i

Do not validate the source script. This option must occur before any other options both on the command line and in the DRIVEINFO_OPTIONS environment variable, otherwise this option will be ignored.

−m

Omit thousands separator.

−p

Pipe this man page to the less command, then quit. All previous options are ignored. This allows the man page to be viewed interactively.

−r

Enable colorized output. ANSI escape codes are used to highlight free space and entries with error codes. No attempt is made to determine if the ANSI escape codes are compatible with the current terminal.

−s

Display execution times. This option is for diagnostic purposes.

−t maximum-entries

Set the maximum number of partition entries allowed in GPT. This option should not be used unless the user knows the GPT was created with more than the default of 128 possible entries.

−v

Display the version, then quit. All previous options are ignored.

−x

Add a metric prefix to the values in the "Size" column.

−z file-list

Install the files associated with this command, then quit. All previous options are ignored. Each character in the argument represents a file type. The list of possible file types is given in the FILES section.

−−

Signals the end of options and disables further option processing.

DEVICES

A device parameter can usually be any of the following:

•

The disk identifier (see below) of a drive with a GPT. Any entry of the form of diskU, where U is zero or a positive decimal integer, e.g. disk0.

•

The device node entry containing the disk identifier of a drive with a GPT. Any entry of the form of /dev/[r]diskU, where U is zero or a positive decimal integer, e.g. /dev/disk0.

Further information about devices can be found on the man page for diskutil(8).

DISK IDENTIFIER

The (BSD) disk identifier string variously identifies a physical or logical device unit, a session (if any) upon that device, a slice (partition) upon that session (if any), or a virtual logical volume. In the context of this command, a disk identifier may take the form of diskU or diskUsS, where:

•

U is the device unit represented by zero or a positive decimal integer (possibly multi-digit). It may refer to hardware (e.g. a hard drive, optical drive, or memory card) or a virtual "drive" constructed by software (e.g. an AppleRAID Set, disk image, CoreStorage LV, etc.).

•

S is the slice (partition) represented by a positive decimal integer (possibly multi-digit). Upon this partition, the raw data that underlies a user-visible file system is usually present, but it may also contain specialized data for certain 3rd-party database programs, or data required for the system software (e.g. EFI partitions, booter partitions, APM partition map data, etc.), or, notably, it might contain backing-store physical volumes for AppleRAID, CoreStorage, APFS, or 3rd-party Storage Systems.

Further information about disk identifiers can be found on the man page for diskutil(8).

COLUMNS

Below is a list of information column types that can be output. The letters may appear as the argument to the c option.

b   Begin:

Base zero beginning offset.

c   Code:

Error codes (see below).

e   End:

Base zero ending offset.

f   Format:

Known or last known file system (user visible) name.

i   Identifier:

Disk identifier of the partition (slice).

m   Mounted:

Either "Yes" for a mounted partition, otherwise "No".

n   Name:

Known or last known volume label.

p   Personality:

Known or last known file system personality name.

s   Size:

If Ending < Beginning, then wrapping is assumed.

t   Type:

Entry type (see below).

ENTRY TYPES

Below is a list of entry types that reserve storage for partitioning information.

PMBR

Protective Master Boot Record

Pri GPT header

Primary GUID Partition Table header

Pri GPT table

Primary GUID Partition Table array

Sec GPT header

Secondary (Backup) GUID Partition Table header

Sec GPT table

Secondary (Backup) GUID Partition Table array

Below is a list of entry types and GUIDs for common partitions. This is not a complete list.

Apple_APFS

7C3457EF-0000-11AA-AA11-00306543ECAC

Apple_Boot

426F6F74-0000-11AA-AA11-00306543ECAC

Apple_CoreStorage

53746F72-6167-11AA-AA11-00306543ECAC

Apple_HFS

48465300-0000-11AA-AA11-00306543ECAC

Bios Boot Partition

21686148-6449-6E6F-744E-656564454649

EFI

C12A7328-F81F-11D2-BA4B-00A0C93EC93B

Linux Filesystem

0FC63DAF-8483-4772-8E79-3D69D8477DE4

Linux LVM

E6D6D379-F507-44C2-A23C-238F2A3DF928

Linux Swap

0657FD6D-A4AB-43C4-84E5-0933C84B4F4F

Microsoft Basic Data

EBD0A0A2-B9E5-4433-87C0-68B6B72699C7

Microsoft Reserved

E3C9E316-0B5C-4DB8-817D-F92DF00215AE

Windows Recovery

DE94BBA4-06D1-4D40-A16A-BFD50179D6AC

ERROR CODES

These letters may appear in the "Code" column.

A

The "Begin" value is not a multiple of the byte-alignment value. This check only performed on partition entries.

I

One or more values are invalid. A value is invalid, if at least one of the three following conditions occurs. First, the "Begin" value is greater than the "End" value. Second, the "Begin" block value is greater than or equal to the number of sectors. Third, the "End" block value is greater than or equal to the number of sectors.

O

The entry overlaps another entry. There is overlap, if at least one of the two following conditions occurs. First, the "End" value is greater than or equal to the "Begin" value of the next entry. Second, the entry is not last and the "Begin" value greater than the "End" value.

S

The "Size" value is not a multiple of the byte-alignment value. This check only performed on partition entries.

COLORS
Red

The entry contains one or more error codes.

Green

The entry represents free space on the drive.

ENVIRONMENT

The following environment variable affects the execution of driveinfo:

DRIVEINFO_OPTIONS

If the DRIVEINFO_OPTIONS variable exists in the environment, then the options are read from this variable, before reading any additional options from the command line.

DRIVEINFO_INCLUDE

The DRIVEINFO_INCLUDE variable is only used during code development. Under normal usage, this variable is not accessed and can therefore be ignored. If the DRIVEINFO_INCLUDE variable exists in the environment during code development, then the directory stored in this variable may be searched for include files.

FILES

The letters given below may appear as the argument to the z option. This option installs the driveinfo command into macOS. Note: Any existing files will be replaced.

c

Copy the bash script to the /usr/local/bin/driveinfo file.

p

Write the man page to the /usr/local/share/man/man8/driveinfo.8 file.

EXAMPLES

driveinfo disk0

If the DRIVEINFO_OPTIONS variable is defined, then the options are read from this variable before displaying the information for disk0.

driveinfo -A disk0

Ignore the DRIVEINFO_OPTIONS variable and display the default information for disk0.

driveinfo -Abdmc bsit /dev/disk0

Replacement for the "sudo gpt -r show /dev/disk0" command.

driveinfo -a 4096 -r disk0

Determine if the "A" and "S" error codes should be issued for partition entries. The argument value of 4096 bytes is the alignment requirement for proper operation of Apple_APFS, Apple_Boot, Apple_CoreStorage and Apple_HFS partitions.

driveinfo -r disk0

Use color to highlight free space and entries with error codes.

driveinfo -R bd disk0

Reset b and d options, if specified in the DRIVEINFO_OPTIONS variable.

driveinfo -z cp

Install this command. See the FILES section for more information.

DIAGNOSTICS

Problems found with entries in (GPT) are flagged by letters appearing in the "Code" column of the table.

The s option can be used to determine the execution times of the script. This options verifies that a majority of the time is spent waiting for the diskutil(8) command to return property lists.

COMPATIBILITY

At the time of this writing, driveinfo found to be compatible with High Sierra (macOS 10.13) and newer versions of macOS.

EXIT STATUS

An value of 0 is returned to indicate success. A value of 2 is returned, if the script determines a error condition. Otherwise, any exit code, found in a diskutil(8) property list, will be the returned exit status of the script.

VALIDATION

Normally, a CRC32 validation is preformed on the source script. This can be disabled with the i option. If the script is deliberately modified, then the hexadecimal value given in the error message should be used to replace the value at the end of the script. This value should be followed by a newline.

SEE ALSO

diskutil(8), gpt(8)

HISTORY

The driveinfo utility is not part of macOS. The first downloadable version appeared in December of 2018.

VERSION

This documentation is current for version 1.0.4 of driveinfo.

BUGS

The tabular information is only produced for drives with a GPT.

The default maximum number of partition entries allowed in GPT is assumed to be 128. While this is a fairly safe assumption, if the actual value is different, then this utility will not know unless set by the t option.

AUTHOR

driveinfo was written by David M. Anderson.

Support and development are available at
https://sourceforge.net/projects/driveinfo/

macOS February 1, 2020 macOS