getbsize(3) get preferred block size

LIBRARY

Lb libbsd

SYNOPSIS

In bsd/stdlib.h Ft char * Fn getbsize int *headerlenp long *blocksizep

DESCRIPTION

The Fn getbsize 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 Fn getbsize produces a warning message.

The Fn getbsize function returns a pointer to a null-terminated string describing the block size, something like ``1K-blocks'' The memory referenced by Fa headerlenp is filled in with the length of the string (not including the terminating null). The memory referenced by Fa blocksizep is filled in with block size, in bytes.

HISTORY

The Fn getbsize function first appeared in BSD 4.4