libadmin: read returns an ssize_t, not a size_t
size_t is unsigned, and therefore can never be less than 0. Using it as
a return code from read() means that we never catch read errors. read()
is defined as returning ssize_t, so just use this to capture its return
code.
Caught by clang's new error messages
Change-Id: Ibf61119dec2c64fd4b1e16e6ef02178e427116f0
Reviewed-on: http://gerrit.openafs.org/7075
Reviewed-by: Derrick Brashear <shadow@dementix.org>
Tested-by: Derrick Brashear <shadow@dementix.org>