The directory command has three options called -min_size, -max_size,
Each of these accepts a size in bytes as value.
> d '***' -min_size=10mb
Such file sizes can be specified either as a plain number, or with one of these units:
|kb||kilobyte||Kilobyte = 1,000 bytes|
|mb||megabyte||Megabyte = 1,000,000 bytes|
|gb||gigabyte||Gigabyte = 1,000,000,000 bytes|
|tb||terabyte||Terabyte = 1,000,000,000,000 bytes|
|pb||petabyte||Petabyte = 1,000,000,000,000,000 bytes|
|eb||exabyte||Exabyte = 1,000,000,000,000,000,000 bytes|
byte unit keywords may be
abbreviated as long as they are unique, typically to two characters.
The default unit is byte, so if you just give a number
without any unit, it will be interpreted as that number of bytes.
Note that the size units have their proper scientific base 10 meanings, so that a kilobyte is 1000 bytes, and not 1024 bytes. For example, the option -min_size=10mb specifies files that have a size of 10,000,000 bytes or more.
There must be at least one digit before the size unit, so 1 megabyte is written as 1mb.
> d *** -min=0.5gb > d *** -min_size=(500 megabyte)List all files that are 500,000,000 bytes or more in size. The parentheses are required in the second example, because there is a (superfluous) space between the number and the size unit.
> d *** -max=0 -nodir > d *** -max_size=0 -nodirectoryList all files that are empty (excluding directory files). This can be a useful command.
> d *** -min=1List all files that are non-empty. Directory files are considered to have a size of 0, so they would not be included in the list.
> d *** -min=987243 -max=987243List all files that are exactly 987,243 bytes in size.
By default, the d directory program prints file sizes in an
appropriate byte unit, such as
kb, Mb, or Gb.
Which unit is selected depends on how large each file is. This makes the directory listing easier to read.
Directory of e:\work\test\ 2 kb 25-Mar-2004 12:37:14 g13_create.cpp 1.6 Mb 23-Sep-2004 19:30:11 g13_create.exe 0 23-Sep-2004 19:30:02 g13_create.lis 123 23-Sep-2004 19:30:12 g13_create.out ---------- 1.6 Mb total, 4 files
Note how large file sizes extend more to the left than small, just like if the sizes had been output as ordinary numbers. This makes the big files stand out better in a long directory listing. It also makes them sortable with a standard sort program.
We can see this by comparing with how the sizes would look as ordinary numbers:
2 kb 25-Mar-2004 12:37:14 g13_create.cpp 1476 25-Mar-2004 12:37:14 g13_create.cpp 1.6 Mb 23-Sep-2004 19:30:11 g13_create.exe 1579160 23-Sep-2004 19:30:11 g13_create.exe 0 23-Sep-2004 19:30:02 g13_create.lis 0 23-Sep-2004 19:30:02 g13_create.lis 123 23-Sep-2004 19:30:12 g13_create.out 123 23-Sep-2004 19:30:12 g13_create.out
These options are used for specifying exactly how file sizes should
be written out, when the
default format is unsuitable.
In the d directory program, they appear as suboptions to the
> d -size=nobyte_unit
|byte_unit [= keyword]||Express file sizes in kb, Mb etc. With -nobyte_unit, they are expressed as plain numbers instead.|
|radix = n||Radix (base) for the number. Default is 10.|
|zero_fill||Fills out the number with leading zeros|
group_separator [= 'c']
|A character like ',' to get numbers written like 1,234|
|width = n||Minimum width in characters. 0 means left adjusted.|
|hide||Hide the item.|
> d -size=nobyte_unit
File sizes are written using the special byte size syntax. Sizes above 1 kb are expressed in the appropriate unit, like kb, Mb, Gb etc.
To suppress this, specify nobyte_unit. The suboptions radix,
group_separator implicitly mean nobyte_unit.
By default, file sizes are printed in an appropriate unit, such as kb or Mb. This is a more readable format than giving the file sizes as ordinary numbers, especially for big files, where it might be difficult to determine the magnitude of the file at a glance.
But sometimes this format is not suitable.
If we are producing a list of files that should be the input to another program, for example, we might want the file sizes as ordinary numbers instead. To achieve this, we use the -size=nobyte option to the directory command.
To get the list with file sizes as ordinary numbers:
> d g13* -files -size=nobyte 1476 e:\work\test\g13_create.cpp 1579160 e:\work\test\g13_create.exe 0 e:\work\test\g13_create.lis 123 e:\work\test\g13_create.out
We can compare this with the default format:
> d g13* -files -size 2 kb e:\work\test\g13_create.cpp 1.6 Mb e:\work\test\g13_create.exe 0 e:\work\test\g13_create.lis 123 e:\work\test\g13_create.out
The -size option without any keyword adds the file sizes
written on the byte size format to the -files listing.
You can write byte_unit=keyword to specify the
smallest unit that should be used.
The valid keywords are the ones listed under Parsing
Byte Sizes, like mb or gigabyte.
With file sizes in megabytes...
> d /size=(byte_unit=megabyte)
Directory of e:\work\html\
0.1 Mb 23-Sep-2004 12:36:01 filespec.html
0.7 Mb 23-Sep-2004 12:36:37 old_glindra.html
0.1 Mb 23-Sep-2004 12:36:58 old_shell.html
0.8 Mb total, 3 files
...and with file sizes in gigabytes:
> d /size=(byte=gig)Note how all file sizes are always rounded upwards, but how the total is calculated on the actual numbers before rounding.
Directory of e:\work\html\
0.1 Gb 23-Sep-2004 12:36:01 filespec.html
0.1 Gb 23-Sep-2004 12:36:37 old_glindra.html
0.1 Gb 23-Sep-2004 12:36:58 old_shell.html
0.1 Gb total, 3 files
See Num Syntax
Options for a full description of the remaining
If you specify one of the numeric options radix,
or group_separator, this implicitly means nobyte_unit.
The file sizes will be printed as regular
Print file sizes as ordinary numbers, with a comma between every third digit.
> d /size=group Directory of e:\work\ 1,604 24-Nov-2004 19:43:49 glindra.cpp 3,950 27-Nov-2004 13:55:29 glindra.hpp 1,694,240 1-Dec-2004 00:10:59 libglindra.a ---------- 1,699,794 total, 3 files
Print file sizes as hexadecimal numbers, with a dash between every third hexadecimal digit.
> d -size=(hex group_separator='-') Directory of e:\work\ 644 24-Nov-2004 19:43:49 glindra.cpp f6e 27-Nov-2004 13:55:29 glindra.hpp 19d-a20 1-Dec-2004 00:10:59 libglindra.a ---------- 19e-fd2 total, 3 files
(Author's note: If you are wondering why anybody would want
do that, or any other weird format, my answer is that probably nobody
does. But the flexibility in how numbers can be written came for free
with the package that was used in the implementation, so it's available
in case there are in fact some real world uses for it.)