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DELAY.REX: Difference between revisions

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DELAY.REX (view source)

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added a comment concerning fractional seconds.
(adjusted SLEEP time for specific systems. -- ~~~~)
m (added a comment concerning fractional seconds.)
 
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This the   '''DELAY.REX'''   REXX program which emulates the   '''delay''' bif  BIF function foras someimplemented by the PC/REXX programsand Personal REXX interpreters.
<lang rexx>/**/trace o;parse arg !;if !all(arg()) then exit;if !cms then address '';signal on halt;signal on novalue;signal on syntax
 
This REXX program (below) will work with most REXXes:
/*┌────────────────────────────────────────────────────────────────────┐
:::* CMS REXX
┌─┘ └─┐▼
:::* PC/REXX &nbsp; (see note)
│ The DELAY function to delay a specific amount of (wall-clock) time │
:::* Personal REXX &nbsp; (see note)
│ (specified in whole seconds). │▼
:::* REGINA REXX
│ │▼
:::* ROO REXX
│ If the REXX program invoking DELAY function is running under PC/REXX,│
:::* R4 REXX
│ this REXX routine should never be invoked as PC/REXX has its own built-│
:::* TSO REXX
│ in function (BIF). │
:::* (Microsoft) DOS
└─┐ ┌─┘
:::* (Microsoft) Windows
└────────────────────────────────────────────────────────────────────┘*/
:::* any system that supports the PING command
in conjunction with the following program (either external or imbedded).
 
<br>Note: &nbsp; when PC/REXX or Personal REXX are used, those REXXes already have a built-in function (BIF), so the &nbsp; '''delay''' &nbsp; subroutine (below) will never be executed, but the REXX &nbsp; '''DELAY''' &nbsp; BIF will be used instead.
@cpsleep = 'CP SLEEP' /*point to (CP) SLEEP cmd*/
@ping = 'PING' /*point to the dos PING cmd*/▼
 
For non-Regina REXXes, &nbsp; this REXX program only uses whole seconds &nbsp; (fractional seconds are ignored).
parse var ! n _ /*parse argument from parms*/
if _\=='' | arg()>1 then call er 59 /*are there too many args? */
if n=='' then n=1 /*no arg? Then assume 1 sec*/
if \isnum(n) then call er 53,dsec 'delay-seconds' /*is n numeric?*/
n=n/1 /*remove any decimal point.*/
if n<=0 then return 0
 
=={{header|REXX}}==
/*┌─────────────────────────────┐
<lang rexx> select▼
│ delay nn seconds. │
when !cms then @cpsleep n "SEC" /*Is this CMS? Use CP SLEEP. */
└─────────────────────────────┘*/
return 0 when !tso then call sleep n /*Is this TSO? Use /*return a zeroSLEEP valuecmd. */▼
 
▲┌─┘ when !regina then do /*Is this Regina? └─┐*/
▲ select
when !cms if nFrac=n then @cpsleepcall sleep n%1 "SEC" /*CMSwhole seconds? Use CP SLEEP*/
when !tso then call sleep n%1 / else call beep 32767, nFrac *TSO? 1000 Use SLEEP/*uses fraction. */
when !regina then call sleep n%1 /*Regina? Use[↑] sound MAY be heard, faint SLEEPtic.*/
when !dos then @ping '-n' n "127.0.0.1 > NUL" /*DOS? use PING */end
when !dos then @ping @pingArgs /*Is this DOS? Use PING command.*/
otherwise nop
▲@ping otherwise = 'PING' nop /*pointdon't toknow thewhat dosthis PINGenvironment cmdis.*/
end /*select*/
 
▲return 0 /*return a zero value. */
 
▲│return 0 /*return a zero value (if a │function).*/
 
 
▲│halt: (specifiedreturn in1 whole seconds). /*return a zero value (if a │function).*/
 
/*══════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════*/
!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=13=='f0f3'x; if !crx then !env='DOS'; 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'; !crx=left(!sys,6)=='DOSCRX'; call !rex; return▼
!var: call !fid; if !kexx then return space( dosenv( arg(1) ) ); return space( value( arg(1), , !env) )▼
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▼
p: return word( arg(1), 1)▼
halt: call er .1▼
isnumisNum: return datatype( arg(1), 'N')▼
novaluenoValue: !sigl=sigl; call er 17, !fid(2) !fid(3) !sigl condition('D') sourceline(!sigl)▼
syntax: !sigl=sigl; call er 13, !fid(2) !fid(3) !sigl !cal() condition('D') sourceline(!sigl)</lang>▼
 
Coding note: &nbsp; the &nbsp; '''!<small>xxx</small>''' &nbsp; subroutines (above) deal mostly with determining what version of REXX is being invoked and what operating system is being used; &nbsp; and based on that information, appropriate flags (variables) are set. &nbsp; This is an example of a robust boilerplate code checking for various versions of REXX and operating systems, and it also defines additional flags not used within this particular program.
 
Programming note: &nbsp; The subroutine &nbsp; '''$ERR''' &nbsp; isn't included here; &nbsp; so here is the gist of the error messages:
/*═════════════════════════════general 1-line subs════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════════*/
::* &nbsp; '''er 59''' &nbsp; &nbsp; &nbsp; too many arguments specified for the ─── DELAY ─── command.
▲!all:!!=!;!=space(!);upper !;call !fid;!nt=right(!var('OS'),2)=='NT';!cls=word('CLS VMFCLEAR CLRSCREEN',1+!cms+!tso*2);if arg(1)\==1 then return 0;if wordpos(!,'? ?SAMPLES ?AUTHOR ?FLOW')==0 then return 0;!call=']$H';call '$H' !fn !;!call=;return 1
::* &nbsp; '''er 53''' &nbsp; &nbsp; &nbsp; argument ─── xxx ─── isn't numeric for the option ─── delay-seconds ─── for the ─── DELAY ─── command.
▲!cal: if symbol('!CALL')\=="VAR" then !call=;return !call
▲!env: !env='ENVIRONMENT';if !sys=='MSDOS'|!brexx|!r4|!roo then !env='SYSTEM';if !os2 then !env='OS2'!env;!ebcdic=1=='f0'x;return
▲!fid: parse upper source !sys !fun !fid . 1 . . !fn !ft !fm .;call !sys;if !dos then do;_=lastpos('\',!fn);!fm=left(!fn,_);!fn=substr(!fn,_+1);parse var !fn !fn '.' !ft;end;return word(0 !fn !ft !fm,1+('0'arg(1)))
▲!rex: parse upper version !ver !vernum !verdate .;!brexx='BY'==!vernum;!kexx='KEXX'==!ver;!pcrexx='REXX/PERSONAL'==!ver|'REXX/PC'==!ver;!r4='REXX-R4'==!ver;!regina='REXX-REGINA'==left(!ver,11);!roo='REXX-ROO'==!ver;call !env;return
▲!sys: !cms=!sys=='CMS';!os2=!sys=='OS2';!tso=!sys=='TSO'|!sys=='MVS';!vse=!sys=='VSE';!dos=pos('DOS',!sys)\==0|pos('WIN',!sys)\==0|!sys=='CMD';call !rex;return
▲!var: call !fid;if !kexx then return space(dosenv(arg(1)));return space(value(arg(1),,!env))
▲er: parse arg _1,_2;call '$ERR' "14"p(_1) p(word(_1,2) !fid(1)) _2;if _1<0 then return _1;exit result
▲p: return word(arg(1),1)
▲halt: call er .1
isint: return datatype(arg(1),'W')
▲isnum: return datatype(arg(1),'N')
▲novalue:!sigl=sigl;call er 17,!fid(2) !fid(3) !sigl condition('D') sourceline(!sigl)
▲syntax: !sigl=sigl;call er 13,!fid(2) !fid(3) !sigl !cal() condition('D') sourceline(!sigl)</lang>
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