Domain/OS calls: swt

Domain/OS calls: swt_$

swt_$ == ??

swt_$close swt_$delarg swt_$fclose swt_$fconn swt_$fcopy swt_$getnow swt_$gtypfd swt_$isatty swt_$note swt_$pack swt_$ptoc swt_$putint swt_$putlit swt_$putlng swt_$seek swt_$trunc swt_$unpack