statvfs question

[Mike Lovell]

i'm working on a program that uses a statvfs call to check the space 
free, space used, and total space on a filesystem. when looking through 
the docs for statvfs, i see that there is f_bsize and f_frsize that 
define block size and 'fundamental file system block size' or fragment 
size. it also has f_blocks which is the number of f_frsize units in the 
file system. i'm wondering about the f_bfree and f_bavail numbers 
though. are these supposed to be in terms of f_bsize or f_frsize? since 
its talking about blocks with these items and some of the docs refer to 
f_frsize as fragment size, i'm guessing that they are in terms of 
f_bsize. but it doesn't seem all that clear to me. anyone know for sure 
what this is supposed to be? thanks.

mike