Manual browser: getbsize(3)

GETBSIZE(3) Library Functions Manual GETBSIZE(3)


getbsizeget user block size


Standard C Library (libc, -lc)


#include <stdlib.h>

char *
getbsize(int *headerlenp, long *blocksizep);


The getbsize function determines the user's preferred block size based on the value of the “BLOCKSIZE” environment variable; see environ(7) for details on its use and format.

The getbsize function returns a pointer to a NUL terminated string describing the block size, something like “1K-blocks”. If the headerlenp parameter is not NULL the memory referenced by headerlenp is filled in with the length of the string (not including the terminating NUL). If the blocksizep parameter is not NULL the memory referenced by blocksizep is filled in with block size, in bytes.

If the user's block size is unreasonable, a warning message is written to standard error and the returned information reflects a block size of 512 bytes.


The getbsize function first appeared in 4.4BSD.
May 30, 2003 NetBSD 7.0