A few functions in sb-posix don't correspond directly to their C
counterparts.
getcwd
— Function: sb-posix:getcwd
Returns the process's current working directory as a string.
readlink
— Function: sb-posix:readlink pathspec
Returns the resolved target of a symbolic link as a string.
syslog
— Function: sb-posix:syslog priority format &rest args
Send a message to the syslog facility, with severity level
priority. The message will be formatted as by cl:format (rather
than C's printf) with format string format and arguments args.