FreeBSD manual
download PDF document: getbsize.3.pdf
GETBSIZE(3) FreeBSD Library Functions Manual GETBSIZE(3)
NAME
getbsize - get preferred block size
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h>
char *
getbsize(int *headerlenp, long *blocksizep);
DESCRIPTION
The getbsize() function returns a preferred block size for reporting by
system utilities df(1), du(1) and ls(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
df(1), du(1), ls(1), systat(1), environ(7)
HISTORY
The getbsize() function first appeared in 4.4BSD.
FreeBSD 14.0-RELEASE-p11 June 11, 2017 FreeBSD 14.0-RELEASE-p11