topic Re: Checking Authentication in SAS in SAS Programming

Checking Authentication in SAS

Aditi24 — Thu, 14 Apr 2016 08:33:33 GMT

Hi,

I am authenticating to the UNIX server using the below statements:-

proc printto log='C:\Temp\sastest.log' new;
run;
%let remote=lwstv21.__8015; signon remote=&remote cscript='C:\Script\tcpunix93.scr';
data _null_;
time_slept=sleep(20,1); 
tday=today();
current=time();
put 'Execution time : ' current=time. tday date9. ;
run;
signoff;
proc printto;
run;

My userid and password details are already in the tcpunix93.scr file and this script has been automated.

But I need to make some changes in the code such that if the signon fails it retries signing on 2 more times . I dont want to read the log file everytime since it will bring much overhead to the code. Please suggest me a way to achieve this requirement.Thanks!

Re: Checking Authentication in SAS

Kurt_Bremser — Thu, 14 Apr 2016 09:05:55 GMT

The best place to do this is the .scr file that controls the logon process (C:\Script\tcpunix93.scr in your case). The syntax for this file is described in the SAS/CONNECT documentation.

You will have to manually replay the logon process with telnet so you can see the responses you get from the remote server; you can then code corresponding reactions into the .scr file.

I did that to catch the "password expired" message delivered by AIX and consequently prompt the user for a new password.

Re: Checking Authentication in SAS

SASKiwi — Thu, 14 Apr 2016 09:19:49 GMT

An alternative to @Kurt_Bremser's approach could be using macro and using the RLINK function (untested):

%macro repeat_signon ( remote = &remote
                      ,repeat = 3);
%let rc = 0;
%let I = 0;
%do %until(&I = &repeat or &rc ne 0);
%let I = %eval(&I+1);
signon remote=&remote cscript='C:\Script\tcpunix93.scr';

data _null_;
  remote_session = optgetc(“&remote”);
  Msg = sysmsg();
  put msg =  remote_session =;
  rc=rlink(remote_session);
  if rc = 0 then put 'No link exists.';
  else put 'A link exists.';
  call symputx(‘rc’, put(rc,2.));
run;
%end;
%mend repeat_signon;

%repeat_signon (remote =%str(lwstv21.__8015));

Re: Checking Authentication in SAS

Aditi24 — Thu, 14 Apr 2016 10:51:32 GMT

Hi @SASKiwi,

The code is giving below error:-

68
ERROR 68-185: The function OPTGETC is unknown, or cannot be accessed.

2883 Msg = sysmsg();
2884 put msg = remote_session =;
2885 rc= rlink(remote_session);
-----
68
ERROR 68-185: The function RLINK is unknown, or cannot be accessed.

2886 if rc = 0 then put 'No link exists.';
2887 else put 'A link exists.';
2888 call symputx('rc', put(rc,2.));
2889 run;

Re: Checking Authentication in SAS

Kurt_Bremser — Thu, 14 Apr 2016 11:08:29 GMT

The rlink() function is only present in SCL, so it won't be of much help outside a DMS SAS. An one would need to have SAS/AF licensed to build a SCL program.

Re: Checking Authentication in SAS

BrunoMueller — Thu, 14 Apr 2016 15:27:51 GMT

Check the doc for SIGNON Statement and Command. The SIGNON statement provides the CMACVAR option to name a macro variable that will tell you the follwoing:

CMACVAR Macro Variable Values in SIGNON
Value	Description
`0`	The sign-on is complete.
`1`	The sign-on failed.
`2`	You have already signed on to the current server session.
`3`	The sign-on is in progress.

Note: If the SIGNON command or statement fails because of incorrect syntax, the macro variable is not set.

Bruno

Re: Checking Authentication in SAS

SASKiwi — Thu, 14 Apr 2016 20:03:10 GMT

Sorry, most SCL functions work in the DATA step but obviously not that one. Perhaps try @BrunoMueller's suggestion in the same macro:

%macro repeat_signon ( remote = &remote
                      ,repeat = 3);
%let rc = 99;
%let I = 0;
%do %until(&I = &repeat or &rc = 0);
%let I = %eval(&I+1);
signon remote=&remote cscript='C:\Script\tcpunix93.scr' CMACVAR = signonrc;
%let rc = &signonrc;

data _null_;
  remote_session = optgetc(“&remote”);
  Msg = sysmsg();
  put msg =  remote_session =;
  if symget('rc') = 0 then put 'A link exists.';
  else put 'A link does not exist.';
run;
%end;

%mend repeat_signon;

%repeat_signon (remote =%str(lwstv21.__8015));

Re: Checking Authentication in SAS

Aditi24 — Tue, 19 Apr 2016 10:33:00 GMT

Thanks @SASKiwi, you are a saviour.

Re: Checking Authentication in SAS

Aditi24 — Tue, 19 Apr 2016 10:33:28 GMT

Thanks @BrunoMueller