coreutils/doc/coreutils.texi

267 * sum invocation::               Print checksum and block counts
339 * mknod invocation::             Make block or character special files
662 @option{--block-size=si}.  Use the @option{-h} or
675 This option is equivalent to @option{--block-size=human-readable}.
800 * Block size::                   BLOCK_SIZE and @option{--block-size}.
896 @cindex block size
899 @command{ls}) display sizes in ``blocks''.  You can adjust the block size
900 and method of display to make sizes easier to read.  The block size
901 used for display is independent of any file system block size.
902 Fractional block counts are rounded up to the nearest integer.
904 @opindex --block-size=@var{size}
910 @vindex POSIXLY_CORRECT@r{, and block size}
912 The default block size is chosen by examining the following environment
913 variables in turn; the first one that is set determines the block size.
918 This specifies the default block size for the @command{df} command.
923 This specifies the default block size for all three commands, if the
927 This specifies the default block size for all values that are normally
936 @env{BLOCKSIZE} is set, but this variable is set, the block size
941 If none of the above environment variables are set, the block size
943 change in the future.  For @command{ls} file sizes, the block size
949 A block size specification can be a positive integer specifying the number
950 of bytes per block, or it can be @code{human-readable} or @code{si} to
966 A block size specification preceded by @samp{'} causes output sizes to
969 American English locale, @samp{--block-size="'1kB"} would cause a size
974 An integer block size can be followed by a suffix to specify a
984 the output.  For example, @samp{--block-size="kB"} displays 3000 as
1064 @opindex --block-size
1069 @option{--block-size=@var{size}} option.  The @option{-k}
1070 option is equivalent to @option{--block-size=1K}, which
1073 @option{--block-size=human-readable}.  The @option{--si} option is
1074 equivalent to @option{--block-size=si}.  Note for @command{ls}
1076 apparent file sizes, whereas the @option{--block-size} option does.
3775 * sum invocation::              Print checksum and block counts.
3946 @section @command{sum}: Print checksum and block counts
7963 @samp{--block-size="'1"} prints a byte count with the thousands
7968 for all files in that directory.  The block size currently defaults to 1024
7981 block special file
8401 Set the default block size to its normal value of 1024 bytes,
8403 (@pxref{Block size}).  If @option{--block-size},
8408 per-directory block count written in long format,
9385 @command{dd} copies input to output with a changeable I/O block size,
9401 Read an input block.
9404 If converting via @samp{sync}, pad as needed to meet the input block size.
9405 Pad with spaces if converting via @samp{block} or @samp{unblock}, NUL
9410 is given, output the data as a single block and skip all remaining steps.
9418 If any of the conversions @samp{swab}, @samp{block}, @samp{unblock},
9422 block boundaries.
9426 and output each output block in turn.  Do not pad the last output block;
9447 @cindex block size of input
9448 @cindex input block size
9449 Set the input block size to @var{bytes}.
9450 This makes @command{dd} read @var{bytes} per block.
9455 @cindex block size of output
9456 @cindex output block size
9457 Set the output block size to @var{bytes}.
9458 This makes @command{dd} write @var{bytes} per block.
9463 @cindex block size
9464 Set both input and output block sizes to @var{bytes}.
9465 This makes @command{dd} read and write @var{bytes} per block,
9469 even if it is smaller than the block size.
9473 @cindex block size of conversion
9474 @cindex conversion block size
9477 Set the conversion block size to @var{bytes}.
9479 (@option{conv=block}) or the reverse (@option{conv=unblock}),
9488 as a byte count rather than a block count.
9498 as a byte count rather than a block count.
9506 interpret @var{n} as a byte count rather than a block count;
9536 when processing each input block.  Statistics are output
9553 and @var{p} partial blocks.  A partial block occurs when a read or
9554 write operation succeeds but transfers less data than the block size.
9557 @samp{conv=block} processing truncated one or more input records.
9582 This implies @samp{conv=block}; trailing spaces are added
9596 @item block
9597 @opindex block @r{(space-padding)}
9604 Remove any trailing spaces in each @samp{cbs}-sized input block,
9607 The @samp{block} and @samp{unblock} conversions are mutually exclusive.
9644 Pad every input block to size of @samp{ibs} with trailing zero bytes.
9645 When used with @samp{block} or @samp{unblock}, pad with spaces instead of
9847 may return early if a full block is not available.
9849 of the block.
9854 interpreted as a block count rather than a count of read operations.
9877 standard block size suffixes like @samp{k}=1024 (@pxref{Block size}).
9883 Any block size you specify via @samp{bs=}, @samp{ibs=}, @samp{obs=}, @samp{cbs=}
9889 block size, you can use a numeric string @var{n} that ends in the
10680 multiple of the file system block size to fully erase the slack space in
10681 the last block of the file.  This space may contain portions of the current
10722 of all zeros, and thereby does not clear all bytes in a block.
10774 * mknod invocation::            Make block or character special files.
11205 @section @command{mknod}: Make block or character special files
11208 @cindex block special files, creating
11211 @command{mknod} creates a FIFO, character special file, or block special
11219 @cindex block special files
11227 time or a ``block'' (many characters) at a time, hence we say there are
11228 @dfn{block special} files and @dfn{character special} files.
11242 @opindex b @r{for block special file}
11243 for a block special file
11255 When making a block or character special file, the major and minor
12185 if there is another mount entry of a real block device for that mount point with
12217 @itemx --block-size=@var{size}
12219 @opindex --block-size
12235 List inode usage information instead of block usage.  An inode (short
12242 Print sizes in 1024-byte blocks, overriding the default block size
12244 This option is equivalent to @option{--block-size=1K}.
12308 The fields for block and inodes statistics are affected by the scaling
12347 The default block size and output format are unaffected by the
12349 variables.  However, the default block size is still affected by
12506 or more generally, @code{ls -l --block-size=1} or @code{stat --format=%s}.
12525 @itemx --block-size=@var{size}
12527 @opindex --block-size
12536 Equivalent to @code{--apparent-size --block-size=1}.
12577 List inode usage information instead of block usage.
12583 @option{-x}; however, passing other options regarding the block size, for
12589 Print sizes in 1024-byte blocks, overriding the default block size
12591 This option is equivalent to @option{--block-size=1K}.
12613 Print sizes in 1,048,576-byte blocks, overriding the default block size
12615 This option is equivalent to @option{--block-size=1M}.
12943 @item %B -- The size in bytes of each block reported by @samp{%b}
12990 the containing device, and so are only defined for character and block
13048 @item %S -- Fundamental block size (for block counts)
13650 @cindex block special check
13651 True if @var{file} exists and is a block special device.
14743 >   # Safe to use $file only within this block.  Use quotes,
15777 block without @code{-drain} being specified.
17915 @item --block-signal[=@var{sig}]
18590 For example @code{fread} will still block until @code{EOF} or error,
19267 $ df --block-size=1 | numfmt --field 2 --header --to=iec | head -n4