getvfsstat() returns information about all mounted file systems.
buf is a pointer to an array of
statvfs structures defined in
statvfs(5).
The buffer is filled with an array of
statvfs structures, one for each mounted file system up to the size specified by
bufsize.
If
buf is given as
NULL,
getvfsstat() returns just the number of mounted file systems.
Normally
flags should be specified as
ST_WAIT. If
flags is set to
ST_NOWAIT,
getvfsstat() will return the information it has available without requesting an update from each file system. Thus, some of the information will be out of date, but
getvfsstat() will not block waiting for information from a file system that is unable to respond.