remove default value of strflag args, fix sigprocmask, see #142
explicit default signal for clone, see #142
explicitly default to SEEK_SET for lseek, see #142
change xattr create to be multiflags, see #142
timerfd_create flag defaults to 0, see #142
clock_nanosleep flag defaults to 0, see #142
prctl fixes
exit status defaults to 0, fix #142
remove commented out default 0