FTN77,E,J,Y                                                                     
C   IMSL ROUTINE NAME   - UGETIO                                                
C                                                                               
C-----------------------------------------------------------------------        
C                                                                               
C   COMPUTER            - HP1000/SINGLE                                         
C                                                                               
C   LATEST REVISION     - JUNE 1, 1981                                          
C                                                                               
C   PURPOSE             - TO RETRIEVE CURRENT VALUES AND TO SET NEW             
C                           VALUES FOR INPUT AND OUTPUT UNIT                    
C                           IDENTIFIERS.                                        
C                                                                               
C   USAGE               - CALL UGETIO(IOPT,NIN,NOUT)                            
C                                                                               
C   ARGUMENTS    IOPT   - OPTION PARAMETER. (INPUT)                             
C                           IF IOPT=1, THE CURRENT INPUT AND OUTPUT             
C                           UNIT IDENTIFIER VALUES ARE RETURNED IN NIN          
C                           AND NOUT, RESPECTIVELY.                             
C                           IF IOPT=2, THE INTERNAL VALUE OF NIN IS             
C                           RESET FOR SUBSEQUENT USE.                           
C                           IF IOPT=3, THE INTERNAL VALUE OF NOUT IS            
C                           RESET FOR SUBSEQUENT USE.                           
C                NIN    - INPUT UNIT IDENTIFIER.                                
C                           OUTPUT IF IOPT=1, INPUT IF IOPT=2.                  
C                NOUT   - OUTPUT UNIT IDENTIFIER.                               
C                           OUTPUT IF IOPT=1, INPUT IF IOPT=3.                  
C                                                                               
C   PRECISION/HARDWARE  - SINGLE/ALL                                            
C                                                                               
C   REQD. IMSL ROUTINES - NONE REQUIRED                                         
C                                                                               
C   NOTATION            - INFORMATION ON SPECIAL NOTATION AND                   
C                           CONVENTIONS IS AVAILABLE IN THE MANUAL              
C                           INTRODUCTION OR THROUGH IMSL ROUTINE UHELP          
C                                                                               
C   REMARKS      EACH IMSL ROUTINE THAT PERFORMS INPUT AND/OR OUTPUT            
C                OPERATIONS CALLS UGETIO TO OBTAIN THE CURRENT UNIT             
C                IDENTIFIER VALUES. IF UGETIO IS CALLED WITH IOPT=2 OR          
C                IOPT=3, NEW UNIT IDENTIFIER VALUES ARE ESTABLISHED.            
C                SUBSEQUENT INPUT/OUTPUT IS PERFORMED ON THE NEW UNITS.         
C                                                                               
C   COPYRIGHT           - 1978 BY IMSL, INC. ALL RIGHTS RESERVED.               
C                                                                               
C   WARRANTY            - IMSL WARRANTS ONLY THAT IMSL TESTING HAS BEEN         
C                           APPLIED TO THIS CODE. NO OTHER WARRANTY,            
C                           EXPRESSED OR IMPLIED, IS APPLICABLE.                
C                                                                               
C-----------------------------------------------------------------------        
C                                                                               
      SUBROUTINE UGETIO(IOPT,NIN,NOUT)                                          
C                                  SPECIFICATIONS FOR ARGUMENTS                 
      INTEGER            IOPT,NIN,NOUT                                          
C                                  SPECIFICATIONS FOR LOCAL VARIABLES           
      INTEGER            NIND,NOUTD                                             
      DATA               NIND/7/,NOUTD/6/                                       
C                                  FIRST EXECUTABLE STATEMENT                   
      IF (IOPT.EQ.3) GO TO 10                                                   
      IF (IOPT.EQ.2) GO TO 5                                                    
      IF (IOPT.NE.1) GO TO 9005                                                 
      NIN = NIND                                                                
      NOUT = NOUTD                                                              
      GO TO 9005                                                                
    5 NIND = NIN                                                                
      GO TO 9005                                                                
   10 NOUTD = NOUT                                                              
 9005 RETURN                                                                    
      END