OpenVMS Source Code Demos
BASIC_TERMINAL_CHARACTERISTICS_DEMO.BAS
1000 %title "Demo_Terminal_Characteristics"
%ident "version 101.1" ! <<<---***
declare string constant k_version = "101.1" !
!========================================================================================================================
! title : Demo_Terminal_Characteristics_xxx.bas
! author : Neil Rieck (https://neilrieck.net)
! history:
! ver who when what
! --- --- ------ --------------------------------------------------------------------------------------------------------
! 100 NSR 050715 1. original work (just hacking around)
! NSR 050716 2. added field definitions from the OpenVMS I/O User's Manual (terminal driver)
! 101 NSR 050718 1. moved the terminal code into a function
!========================================================================================================================
option type=explicit
set no prompt
declare string constant k_program = "Demo_Terminal_Characteristics"
!
external sub access_terminal_characteristics(string,long,long)
!
! variable declarations
!
declare string old_tty_settings$ ,&
debug$ ,&
long debug%
!
!====================================================================================================
! main
!====================================================================================================
main:
print k_program +"_"+ k_version !
print string$(len(k_program +"_"+ k_version), asc("=")) !
!
input "debug level? (0-3) ";debug$ !
when error in !
debug% = integer(debug$) !
use !
debug% = 3 !
end when !
!
print ">>> reading old tty settings"
call access_terminal_characteristics(old_tty_settings$,0,debug%) ! read current settings
sleep 2
print ">>> disabling broadcast"
call access_terminal_characteristics(old_tty_settings$,2,debug%) ! disable broadcast
sleep 2
print ">>> restoring original tty settings"
call access_terminal_characteristics(old_tty_settings$,1,debug%) ! restore original
sleep 2
!
32000 end !
!
!########################################################################################################################
!
! access terminal characteristics
!
! switch% 0 = read tty characteristics into terminal_char_bits$
! 1 = write tty characteristics from terminal_char_bits$
! 2 = use terminal_char$ as a template to disable broadcasts
!
32100 sub access_terminal_characteristics(string terminal_char_bits$, long switch%, long debug%)
option type=explicit
!
%include "starlet" %from %library "sys$library:basic$starlet" ! system services
%include "$ssdef" %from %library "sys$library:basic$starlet" ! ss$
%include "$iodef" %from %library "sys$library:basic$starlet" ! io$
%include "$ttdef" %from %library "sys$library:basic$starlet" ! tt$
%include "$tt2def" %from %library "sys$library:basic$starlet" ! tt2$
%include "lib$routines" %from %library "sys$library:basic$starlet" ! lib$
%include "$libdef" %from %library "sys$library:basic$starlet" ! eg. lib$_normal
%include "$dvidef" %from %library "sys$library:basic$starlet" ! dvi$
!
! record: I/O Status Block
!
record IosbRec ! structure of I/O Status Block
variant
case
group one ! this variation is used with I/O transfers
word rc ! return code
word xfer_count ! transfer count
long long_0 ! device specific info
end group one
case
group two ! this variation is used to satisfy the compiler
basic$quadword quad_0 ! unsigned quad (system calls)
end group two
case
group three ! this variation is used in $SNDJBC + $SNDJBCW
long job_status ! job status
long long_3 ! device specific info
end group three
end variant
end record IosbRec
!
! record: terminal characteristics
!
record tty_chars ! terminal chracteristics buffer layout
variant
case
group one ! for hacking
long DataBitsL(2) ! 0-2 = 3 *4 =12 bytes
end group !
case
group two ! for hacking
byte DataBitsB(11) ! 0-11 =12 bytes
end group !
case
group three !
string DataBits$ = 12 ! 12 bytes
end group !
case
group four ! I/O User's Reference Manual (terminal driver)
byte term_class !
byte term_type !
word page_width !
long basic_char ! TT$M_ stuff; also includes page length
long exten_char ! TT2$M_ stuff
end group
end variant
end record
!
! variable declarations
!
declare word item_w , &
chan_w , &
long rc% , &
junk% , &
item% , &
i% , &
string junk$ , &
terminal_name$
declare IosbRec IosbVar !
declare tty_chars characteristics ! terminal characteristics variable
!
!========================================================================================================================
main:
for i% = 0 to 2 ! init
characteristics::DataBitsL(i%) = 0 !
next i% !
!
! find out the attched device name (usually a terminal but could be a disk if this is a batch job)
!
! LIB$GETDVI item-code [,channel] [,device-name] [,longword-integer-value] [,resultant-string] [,resultant-length]
!
item% = Dvi$_TT_phyDevNam !
rc% = lib$getdvi(item%,,"SYS$INPUT",,terminal_name$,) ! find the input device name (could be disk)
if (rc% and 7%) <> 1 then !
print "-e-lib$getdvi-rc: ";rc% if debug% >= 1 !
goto sub_exit !
end if !
print "-i-name:"; terminal_name$ if debug% >= 2 !
!
! get an i/o channel
!
rc% = sys$assign( terminal_name$, chan_w,,) !
if (rc% and 7%) <> 1 then !
print "-e-sys$assign-rc: ";rc% if debug% >= 1 !
goto sub_exit !
end if !
print "-i-chan: "+str$(chan_w) if debug% >= 2 !
!
! SYS$QIO [efn] ,chan ,func ,[iosb] ,[astadr] ,[astprm] ,[p1] ,[p2] ,[p3] ,[p4] ,[p5] ,[p6]
!
select switch%
case 0 !
item_w = IO$_SENSEMODE
case 1 !
item_w = IO$_SETMODE
characteristics::DataBits$ = terminal_char_bits$ !
case else !
item_w = IO$_SETMODE !
characteristics::DataBits$ = terminal_char_bits$ ! copy
characteristics::basic_char = characteristics::basic_char or tt$m_nobrdcst ! set bit
characteristics::exten_char = characteristics::exten_char and (-1% - tt2$m_brdcstmbx) ! clear bit
end select
rc% = sys$QioW( ! event flag &
,chan_w by value ! channel &
,item_w by value ! function &
,IosbVar::quad_0 by ref ! iosb &
, ! ast address &
, ! ast parameter &
,characteristics::DataBitsL(0) by ref ! p1 buff addr &
,12% by value ! p2 buff length &
,,,, )
if (rc% and 7%) <> 1 then
print "sys$qiow-rc: ";rc% if debug% >=1
goto sub_exit
end if
!
if switch% = 0 then
terminal_char_bits$ = characteristics::DataBits$ ! pass back sensed data
end if
!
if debug% >= 2 then
print "-i-iosb rc : ";str$( IosbVar::rc) ! what was the rc% of the request?
print "-i-iosb cnt: ";str$( IosbVar::xfer_count ) !
print "-i-iosb lng: ";str$( IosbVar::long_0 ) !
end if
!
!~ for i% = 0 to 11
!~ print "debugB: ";characteristics::DataBitsB(i%)
!~ next i%
!
!~ for i% = 0 to 2
!~ print "debugL: "; characteristics::DataBitsL(i%)
!~ next i%
!
if debug% >= 2 then
print "-i-term_class : "; characteristics::term_class
print "-i-term_type : "; characteristics::term_type
print "-i-page_width : "; characteristics::page_width
print "-i-basic_char : "; characteristics::basic_char
print "-i-extended_char: "; characteristics::exten_char
end if
!
sub_exit:
if chan_w <> 0 then ! if we've got a channel assigned...
rc% = sys$dassgn(chan_w) !
if (rc% and 7%) <> 1 then !
print "-e- $dassgn rc: ";rc% if debug% >= 1 !
end if !
end if !
!
end sub
!
Back to HomeNeil Rieck
Waterloo, Ontario, Canada.