From Rosetta Code

The   SCRSIZE.REX   is a REXX program to emulate the   scrsize   bif (which is available under some REXXes) for some REXX programs.

The help for the   SCRSIZE   REXX program is included here ──► SCRSIZE.HEL.

/**/trace o;parse arg !;if !all(arg()) then exit;if !cms then address '';signal on halt;signal on novalue;signal on syntax
┌─┘ └─┐
│ The SCRSIZE function is used to return the screen size (depth and │
│ width) for those REXX interpereters that don't support the SCRSIZE │
│ built-in function (BIF). │
│ │
│ │
│ [PC/REXX, R4, and ROO support the SCRSIZE bif.] │
│ │
│ Method: to save time, this program first attempts to find the DOS │
│ environmental variable LINES and COLUMNS. │
│ │
│ Failing that (in whole or in part), it then parses the results from │
│ the MODE CON (DOS) command and scans for the LINES and COLUMNS │
│ parameters. │
└─┐ ┌─┘

if !cms then do /*if CMS, use $QWHAT pgm. */
'$QWHAT SCRDEPTH , 24';sd=rc /*get sd, default to 24. */
'$QWHAT SCRWIDTH , 80';sw=rc /*get sw, default to 80. */
return sd sw /*return depth and width. */
if \!dos then return 24 80 /*not DOS? Return default.*/
@erase ='ERASE' /*point to dos ERASE cmd*/
@find ='FIND' /*point to the dos FIND cmd*/
@MODE ='MODE' /*point to the dos MODE cmd*/
tfid= /*name of a temporary FID. */
/*Note: /i = ignore case.*/
@find_s ='/i "s"' /*find line with an "s". */
@find_l ='/i "l"' /*find line with an "l". */
parse var !! _ . '(' ops ')' __
if _\=='' | __\=='' then call er 59
do while ops\==''; parse var ops _1 2 1 _ . 1 _o ops; upper _
when _==',' then nop
when _1=='.' & pos("=",_)\==0 then tops=tops _o
when abbn('SCRWIDths' )|,
abbn('WIDths' )|,
abbn('WIDes' )|,
abbn('WIDs' )|,
abbn('COLums' )|,
abbn('COLs' ) then findcols=no()
when abbn('SCRWIDTHs' )|,
abbn('DEPTHs' )|,
abbn('DEPs' )|,
abbn('ROWs' )|,
abbn('LINEs' )|,
abbn('LINESizes' ) then findrows=no()
otherwise call er 55,_o
/*──────────────attempt to use the DOS environmental variable: COLUMNS. */
if findcols then do
sw=p(!var('COLUMNS')) /*pick off the first word. */
if \isint(sw) then sw=0 /*if not whole #, then 0. */
sw=sw/1 /*decimal point ? remove.*/
/*──────────────attempt to use the DOS environmental variable: LINES. */
if findrows then do
sd=p(!var('LINES')) /*pick off the first word. */
if \isint(sd) then sd=0 /*if not whole #, then 0. */
sd=sd/1 /*decimal point ? remove.*/
/*──────────────if not defined, then use (DOS) MODE (writes to a file). */
if sd==0 | sw==0 then /*not defined? use MODE. */
do /*first, find temp. disk. */
call gettfid ,'$$$' /*get a TEMP id:  !fn $$$ */
@mode 'con', /*issue MODE CON, then: */
'|' @find @find_s, /*find lines with an "s", */
'|' @find @find_l '>' tfid /*find lines with an "l". */
call linein tfid,1,0 /*point to record 1. */
do while sd==0 | sw==0 /*read file while sw|sw =0.*/
if lines(tfid)==0 then leave /*No lines left? We're done*/
_=translate(linein(tfid),,'=:') /*translate = : --> blanks.*/
parse upper var _ yname yval . /*parse with name value. */
if yname=='COLUMNS' & sw==0 then sw=yval /*if COLUMNS, it's width.*/
if yname=='LINES' & sd==0 then sd=yval /*if LINES, it's depth.*/
end /*do while*/
@erase tfid /*erase the temp. file. */
if sd==0 then sd=50 /*just in case MODE failed.*/
if sw==0 then sw=80 /*just in case MODE failed.*/
/*use positive values. */
return abs(sd) abs(sw) /*return depth and width. */
/*═════════════════════════════general 1-line subs════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════*/
!all:!!=!;!=space(!);upper !;call !fid;!nt=right(!var('OS'),2)=='NT';!cls=word('CLS VMFCLEAR CLRSCREEN',1+!cms+!tso*2);if arg(1)\==1 then return 0;if wordpos(!,'? ?SAMPLES ?AUTHOR ?FLOW')==0 then return 0;!call=']$H';call '$H' !fn !;!call=;return 1
!cal:if symbol('!CALL')\=="VAR" then !call=;return !call
!env:!env='ENVIRONMENT';if !sys=='MSDOS'|!brexx|!r4|!roo then !env='SYSTEM';if !os2 then !env='OS2'!env;!ebcdic=1=='f0'x;return
!fid:parse upper source !sys !fun !fid . 1 . . !fn !ft !fm .;call !sys;if !dos then do;_=lastpos('\',!fn);!fm=left(!fn,_);!fn=substr(!fn,_+1);parse var !fn !fn '.' !ft;end;return word(0 !fn !ft !fm,1+('0'arg(1)))
!rex:parse upper version !ver !vernum !verdate .;!brexx='BY'==!vernum;!kexx='KEXX'==!ver;!pcrexx='REXX/PERSONAL'==!ver|'REXX/PC'==!ver;!r4='REXX-R4'==!ver;!regina='REXX-REGINA'==left(!ver,11);!roo='REXX-ROO'==!ver;call !env;return
!sys:!cms=!sys=='CMS';!os2=!sys=='OS2';!tso=!sys=='TSO'|!sys=='MVS';!vse=!sys=='VSE';!dos=pos('DOS',!sys)\==0|pos('WIN',!sys)\==0|!sys=='CMD';call !rex;return
!var:call !fid;if !kexx then return space(dosenv(arg(1)));return space(value(arg(1),,!env))
$fact!:procedure;parse arg x _ .;l=length(x);n=l-length(strip(x,'T',"!"));if n<=-n|_\==''|arg()\==1 then return x;z=left(x,l-n);if z<0|\isint(z) then return x;return $fact(z,n)
$fact:procedure;parse arg x _ .;arg ,n ! .;n=p(n 1);if \isint(n) then n=0;if x<-n|\isint(x)|n<1|_||!\==''|arg()>2 then return x||copies("!",max(1,n));!=1;s=x//n;if s==0 then s=n;do j=s to x by n;!=!*j;end;return !
$sfxa:parse arg ,s,m;arg u,c;if pos(left(s,2),u)\==0 then do j=length(s) to compare(s,c)-1 by -1;if right(u,j)\==left(c,j) then iterate;_=left(u,length(u)-j);if isnum(_) then return m*_;leave;end;return arg(1)
$sfxf:parse arg y;if right(y,1)=='!' then y=$fact!(y);if \isnum(y) then y=$sfxz();if isnum(y) then return y;return $sfxm(y)
$sfxm:parse arg z;arg w;b=1000;if right(w,1)=='I' then do;z=shorten(z);w=z;upper w;b=1024;end;p=pos(right(w,1),'KMGTPEZYXWVU');if p==0 then return arg(1);n=shorten(z);r=num(n,f,1);if isnum(r) then return r*b**p;return arg(1)
$sfxz:return $sfxa($sfxa($sfxa($sfxa($sfxa($sfxa(y,'PAIRs',2),'DOZens',12),'SCore',20),'GREATGRoss',1728),'GRoss',144),'GOOGOLs',1e100)
abb:arg abbu;parse arg abb;return abbrev(abbu,_,abbl(abb))
abbl:return verify(arg(1)'a',@abc,'M')-1
abbn:parse arg abbn;return abb(abbn)|abb('NO'abbn)
er:parse arg _1,_2;call '$ERR' "14"p(_1) p(word(_1,2) !fid(1)) _2;if _1<0 then return _1;exit result
err:call er '-'arg(1),arg(2);return ''
erx:call er '-'arg(1),arg(2);exit ''
getdtfid:tfid=p(!var("TMP") !var('TEMP') homedrive()"\");if substr(tfid,2,1)==':'&substr(tfid,3,1)\=="\" then tfid=insert('\',t,2);return strip(tfid,'T',"\")'\'arg(1)'.'arg(2)
gettfid:if tfid\=='' then return tfid;gfn=word(arg(1) !fn,1);gft=word(arg(2) 'ANS',1);tfid='TEMP';if !tso then tfid=gfn'.'gft;if !cms then tfid=gfn','gft",A4";if !dos then tfid=getdtfid(gfn,gft);return tfid
halt:call er .1
homedrive:if symbol('HOMEDRIVE')\=="VAR" then homedrive=p(!var('HOMEDRIVE') 'C:');return homedrive
int:int=num(arg(1),arg(2));if \isint(int) then call er 92,arg(1) arg(2);return int/1
isint:return datatype(arg(1),'W')
isnum:return datatype(arg(1),'N')
na:if arg(1)\=='' then call er 01,arg(2);parse var ops na ops;if na=='' then call er 35,_o;return na
nai:return int(na(),_o)
nan:return num(na(),_o)
no:if arg(1)\=='' then call er 01,arg(2);return left(_,2)\=='NO'
novalue:!sigl=sigl;call er 17,!fid(2) !fid(3) !sigl condition('D') sourceline(!sigl)
num:procedure;parse arg x .,f,q;if x=='' then return x;if isnum(x) then return x/1;x=space(translate(x,,','),0);if \isnum(x) then x=$sfxf(x);if isnum(x) then return x/1;if q==1 then return x;if q=='' then call er 53,x f;call erx 53,x f
p:return word(arg(1),1)
s:if arg(1)==1 then return arg(3);return word(arg(2) 's',1)
shorten:procedure;parse arg a,n;return left(a,max(0,length(a)-p(n 1)))
syntax:!sigl=sigl;call er 13,!fid(2) !fid(3) !sigl !cal() condition('D') sourceline(!sigl)