NAME
getbsize —
get preferred block size
LIBRARY
library “libc”
SYNOPSIS
#include
<stdlib.h>
char *
getbsize(int
*headerlenp, long
*blocksizep);
DESCRIPTION
Thegetbsize()
function returns a preferred block size for reporting by system utilities
df(1),
du(1),
ls(1)
and systat(1), based on the value of the BLOCKSIZE
environment variable. BLOCKSIZE may be specified
directly in bytes, or in multiples of a kilobyte by specifying a number
followed by ``K'' or ``k'', in multiples of a megabyte by specifying a number
followed by ``M'' or ``m'' or in multiples of a gigabyte by specifying a
number followed by ``G'' or ``g''. Multiples must be integers.
Valid values of BLOCKSIZE
are 512 bytes to 1 gigabyte. Sizes less than 512 bytes are rounded up to 512
bytes, and sizes greater than 1 GB are rounded down to 1 GB. In each case
getbsize()
produces a warning message via
warnx(3).
The
getbsize()
function returns a pointer to a null-terminated string describing the block
size, something like “1K-blocks”. The memory referenced by
headerlenp is filled in with the length of the string
(not including the terminating null). The memory referenced by
blocksizep is filled in with block size, in bytes.
SEE ALSO
HISTORY
The getbsize() function first appeared in
4.4BSD.