1) optional arguments

3) partial list of section 2 manpages from Debian Linux box: functions
we may want to consider interfaces for.  Some of the obviously
unnecessary/dangerous functions have been deleted from this list, as
have the ones we've already got bindings for, but even so, inclusion
in this list does _not_ imply we've definitely decided something needs
adding.

FD_CLR FD_ISSET FD_SET FD_ZERO accept acct adjtime adjtimex bdflush
bind break brk cacheflush capget capset chroot clone connect creat
create_module delete_module execve exit fcntl fdatasync flock fork
fstat fstatfs fsync ftime ftruncate getcontext getdents getdomainname
getdtablesize getgroups gethostid gethostname getitimer 
getpeername getpriority getrlimit getrusage getsockname getsockopt
gettimeofday gtty idle init_module ioctl ioctl_list ioperm iopl listen
llseek lock lseek lstat madvise mincore mknod mlock mlockall 
modify_ldt mount mprotect mpx mremap msgctl msgget msgop msgrcv msgsnd
munlock munlockall nanosleep nice open pause pipe poll
prctl pread prof profil pselect ptrace pwrite query_module quotactl
read readlink readv reboot recv recvfrom recvmsg rename rmdir
sbrk sched_get_priority_max sched_get_priority_min sched_getparam
sched_getscheduler sched_rr_get_interval sched_setparam
sched_setscheduler sched_yield select semctl semget semop send
sendfile sendmsg sendto setcontext setdomainname setgroups sethostid
sethostname setitimer setpgrp setpriority setrlimit setsid setsockopt
settimeofday sgetmask shmat shmctl shmdt shmget shmop shutdown
 sigaction sigaltstack sigblock siggetmask sigmask signal sigpause
sigpending sigprocmask sigreturn sigsetmask sigsuspend sigvec socket
socketcall socketpair ssetmask stat statfs stime stty swapoff swapon
symlink sync syscalls sysctl sysfs sysinfo syslog time times truncate
ulimit umask umount uname ustat utime utimes vfork vhangup wait wait3
wait4 waitpid write writev

4) In the spec but not implemented: 

- buffers

5) fill out TODO/TBD stuff in the spec

6) sort out exports.  All interface functions, all constants, all
  type coercion functions

7) variable-length functions > like execvp()? Do they take a list, or
vector or either? "Either" sounds good. Which is to say, a sequence.

8) In some cases, errno is used for "normal" exit, not just for
exceptional exit. For example, EINTR, EAGAIN, reading or writing big
buffers, etc... It may be more efficient to just compare two integers
than going thru an exception mechanism that will be invoked everytime.

9) proper alien definitions of structures [ possibly an sb-grovel
problem, but the way we define calls exposes the problem -- see
readdir() ]
