use BUFFSIZE 16M to reduce footprint
use flush before rados rados_shutdown
increase max object size to 32M, use less aio write to save cpu resource
use syncio to implement put-continue
since use syncio, increase the buffer size and max object size  to improve upload speed
use timeout, change max object size to 64M
use SCNu64 for uint64
use git log --oneline for REL number
stdout print success
only when ret==0, output success
return fail if interrupted
if rados_striper_write returns non-zero, report error
the size of stripedobject is not atomic, set it before writing real data

filesize must be bigger than 2 bytes
now striprados get can handle signal
can use TERM signal to stop do_ls
use -d to delete keys from a file
finish do_info