TRANSFERING SAS DATASETS BETWEEN THE PC AND THE MAINFRAME. James Ssemakula Computing Services Center Texas A&M University

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1 TRANSFERING SAS DATASETS BETWEEN THE PC AND THE MAINFRAME. James Ssemakula Computing Services Center Texas A&M University This paper gives a detailed description of the implementation of the SAS Micro-to-Host link at a specific site. In fact, the main body of the paper constitutes a handout given to users to help them in the transfer of SAS datasets. Obviously, it is geared toward users who have only a limited knowledge of computers. It should be easy to modify this handout to suit the needs of other sites. Although the primary focus is on DOS and MVS, much of it remains true for other environments and for SAS/CONNECT. The handout describes a convenient way of transporting SAS datasets between a Personal Computer (PC) and a host mainframe computer at Texas A&M University (TAMU). The versions of SAS it covers are 5.18 on the IBM mainframe (MVSlESA) and 6.04 on the PC (DOS 3.0 or higher). Read the entire document before commencing file transfer. To communicate with the mainframe, your PC and/or communications package should conform to the TAMU communication protocol parameters. At the present time, KERMIT is the only communications package supported by the Computing Services Center. It is provided free of charge at the Help Desk. This document assumes that you use KERMIT. The communications protocol parameters at the TAMU Computing Services Center are: baud=300, 1200,2400 or 9600; 8 data bits; 1 stop bit; full duplex and no parity. The telephone numbers for 1200 baud are and The numbers for 2400 baud are , and baud requires either a direct line or a Data Over Voice (DOV) box. Currently, DOV service is limited to areas with telephone prefixes of 260, 268, 693, 696, 764, 845 and 847. You can upload SAS datasets from your PC to the mainframe using PROC UPLOAD and download SAS datasets from the mainframe>to the PC using PROC DOWNLOAD. The major advantage of using the Micro-to Host-Link is that you do not have to convert the SAS dataset to ASCII format before transferring it. To sucessfully transfer SAS datasets between your PC and the mainframe you need to make one-time changes to three files: C:AUTOEXEC.BAT, C:\SAS\AUTOEXEC.SAS and C:\SAS\SASLlNK\TSO.SCR or CMS.SCR if you wish to transfer to and from VMlCMS. (Note that the C is used merely for purposes of illustration.) Once these permanent changes have been made, perform the following four (4) steps: 1. Log on to TSO. 2. Start PC SAS. 3. Signon to SAS on the mainframe. 4. Run either PROC UPLOAD or PROC DOWNLOAD using the RSUBMIT command. The permanent file changes are described below, followed by a description of each of the four steps for transferring SAS datasets. AUTOEXEC.BAT Making changes to the AUTOEXEC.BAT file is a convenient way of setting up your default parameters whenever you boot your PC. You can use it to tell SAS which communications port your PC is using (1 or 2), baud rate, number of data bits, number of stop bits, and whether or not the asyncronous adapter is being used for a serial interface printer. Include a MODE command in your AUTOEXEC.BAT file to set your default communications parameters. The general form of this one line command is: MODE COMn: baud,parity,databits,stopbit,p where: n either 1 or 2 (asynchronous communication port number). baud 110,150,300,600,1200,2400,4800 or parity either N (none), 0 (odd), E (even). databits either 7 or 8. stopbits either 1 or 2 239

2 For example MODE COM1: 2400,N,8,1,P says that you are using communication port 1 at a baud rate of 2400 with no parity, 8 data bits and one stop bit. This is valid for DOS 3.0 (or higher) and is commonly used to communicate with the mainframe at TAMU. The last parameter (P) indicates that the asynchronous adapter is being used for a serial interface printer. The Mode command has many variations. some of which are dependent on the DOS version. For example, in DOS 4.01, the P option can be used to specify the type of retry action if a port is busy. DOS 4.01 also allows n to go up to 4, and the use of a less cryptic form of the MODE command: COMn BAUD=b DATA=d STOP=s PARITY=p RETRY=r Here the RETRY replaces the P option and r can have a value of E (default), B (equivalent to P), R, or NONE. Consult your DOS manual to see what form of the MODE command you need. If you are uncomfortable with changing your AUTOXEC.BAT file, there are two equally cumbersome alternatives. The first is to enter the MODE command at the C: prompt after you boot up your system every time you need to communicate with the mainframe. The second alternative is to execute the ny. EXE program in your SAS root directory everytime you need to communicate. ny.exe is a menu driven teletype (async) terminal emulator program that is easy to use and offers extra choices. You can choose a method for HANDSHAKING (but you should choose no handshaking), and you can choose between full and half duplex. Of the three methods of setting communications protocol parameters, inserting a line in the AUTOEXEC.BAT file is the recommended method. AUTOEXEC.SAS Making changes to the AUTOEXEC.SAS file is a convenient way of automatically setting your default parameters when you boot up SAS. This is because commands in this file are executed when you start PC SAS for the first time. These commands stay in effect until you change them explicitly. Your AUTOEXEC.SAS is located in your SAS root directory and should contain the the following lines: FILENAME RLINK '!SASROOl\SASLlNK\TSO.SCR' ; L1BNAME MAPS 'C:\SAs\MAPS' ; OPTIONS REMOTE = ASYNC PAGESIZE = 80 L1NESIZE = 100 ; GOPTIONS DEVICE = CGA ; The FILENAME statement is used to assign a fileref (RLlNK) to the path leading to the TSO.SCR script file. likewise, the L1BNAME statement assigns a libref (MAPS) to the location of the map datsets. You may change the PAGESIZE and L1NESIZE parameters in the OPTIONS statement to suit your needs. leave the REMOTE = ASYNC option alone. The GOPTIONS statement is just for your convenience. You may add other parameters like color. It is important that it specifies a device name that matches the graphics adapter card in your Pc. You may also remove it altogether. If you leave it in, your graphs will go to your default graphics device "automatically." In this case, the graphics would be routed to your CGA monitor. Consult the SAS Language Guide and the SAs\GRAPH Guide for Personal Computers for more information about the the OPTIONS and GOPTIONS statements. If you like to bring up SAS using SAS/ASSIST then you should include these same statements in the ASSIST.SAS located in the SASMACRO subdirectory of the SAS directory. TSO.SCR TSO.SCR is a sample file that contains a script for starting or stopping the SAS link via the SIGNON and SIGNOFF commands, respectively. A script is a SAS program written in a specialized set of SAS statements called script statements. In general, it is no trivial matter writing a script file from scratch. Among the functions of script files are to invoke the host SAS system (i.e. bring up SAS on the mainframe), set the REMOTE= option for the host SAS system, define what response is expected from the host and to process the response(s) from the host. TSO.SCR is a script for manual log on. The script for automatic log on is called LOGTSO.SCR. Both files are located in the subdirectory SASLINK of the SAS directory. The TSO.SCR file consists of five parts: ASYNC SIGN ON, ASYNC SIGNOFF, 3270 SIGNOFF, SUBROUTINES, and ERROR HANDLING. The only part that needs editing is the ASYNC SIGN ON. For async (Le. asynchronous) connections, the script sets communication parameters with the BAUD, PARITY, 240

3 STOPBITS, and DATABITS statements. Make sure your ASYNC SIGNON section has the following statements: baud 2400; parity none; stopbits 1; databits 8 ; maxi 512 ; maxo 512; timeout 10 seconds; type "sas options('remote = RSAS7171')" cr ; waitfor 'PACKET': onok, 10 seconds: nosas ; The baud statement used here sets the rate of data transmission at Use a baud rate that matches your hardware and/or software. Files are transferred between computers in segments called packets. The maxi & maxo statements specify the maximum length of these packets in bytes during asynchronous communication. The number of bytes can be any integer from 72 through The size of the packet impacts upon speed of transmission. The smaller the packets the more of them are necessary to transfer the same amount data, but transmission time per packet is less. However, the total time may increase dure to the overhead required to process the extra packets. The pay-off is that fewer errors tend to occur with smaller packets since fewer repeat transmission are needed. In general, you should use smaller values if there is interference in the communication lines. The timeout statement sets the time to wait for a packet from the host before resending the last PC packet. The waitfor statement specifies characters to be received from the host or time to wait for response before proceeding. The remote = RSAS7171 option indicates that an IBM 7171 device is used on the mainframe to provide ASCII to IBM 3270 protocol conversion. Check with your computer center for the right communications device name. Once these permanent changes are completed, reboot your PC arid go through the steps below to upload/download SAS datasets or even non SAS files. 1. LOG ON TO TSO You need to establish an interactive session with the host computer to use the SAS remote link facility. At TAMU, this means using either TSO on the IBM-3090 or VM/CMS on the AMDHAL-S860. This discussion assumes that you are using TSO. Both WYLBUR and TSO access the same files making it easy to share data. (TSO stands for Time Sharing Option; OS stands for Operating System; VM stands for Virtual Machine; and CMS stands for Conversational Monitor System. WYLBUR is an editor on the IBM 3090). Logging on to TSO is straight forward. Use KERMIT (or other communications software) to connect to the mainframe and choose VTAM as your resource name. At the ATM screen choose TSO as your application. When the system asks for your USERID type: USERID PROC(06) SIZE(2000) The USERID is your usual WYLBUR account number, e.g. N123AB. At TAMU, PROC tells the system where SAS is stored. SIZE is the region size (memory) in kilobytes. The above statement is equivalent to: /I EXEC SAS,REGION= 2000K. Enter your password. After TSO gives you the READY prompt, escape back to your PC and exit from KERMIT as usual. 2.SIGNON Start PC SAS. At the command line of any window, issue a SIGN ON command to start the link to the mainframe. You will get a message notifying you that the link has been started. If the link is established, PC SAS starts up SAS on the mainframe and a message is sent back to your LOG window. Now you are ready to start transferring files. Remember to terminate the link by issuing a SIGNOFf command at the command line and to log off from TSO using KERMIT. 241

4 PROC DOWNLOAD/UPLOAD (SUBMIT WITH RSUBMIT). To use these PROCs you need to know a little bit about file handling in TSO (the equivalent of Job Control language -- JCl). The basic information about files (e.g. name, organization and space requirements), is the same under both TSO and WYlBUR (OS batch processing). The differences are in file name specification, file creation and deletion, and how files are made available to a SAS session. These functions are performed by using TSO commands, each of which usually has operands. Below is a partial description of the AllOCATE command. This command is equivalent to the JCl DD statement except that, it is not normally used to supply Data Control Block (DCB) characteristics of a file. These operands (Le. DCBs) are part of the ATTRIB command. Since DCB parameters are not required for SAS version 5.18 datasets, the A TTRIB command is not discussed here. The general format of the ALLOCATE command is: ALLOCATE FILE(DDname) DATASET(,filename') SPACE(primary secondary) unit disposition RELEASE where: FILE DATASET SPACE unit disposition RELEASE specifies the DDname for the dataset. specifies the name of the file. gives the primary and secondary space allocations for the dataset in terms of unit. If you do not need secondary allocation, omit the secondary. is the unit of allocation, e.g. TRACKS and CYLINDERS. describes the status of the dataset being allocated, e.g. NEW CATALOG RELEASE. releases any unused space at the end of the dataset when the dataset is freed. The same may be achieved by using PROC RELEASE. Examples of a TSO command: ALLOCATE FILE(lNl) DATASET('USR.N123.AB.SASDATA') SHR ALLOCATE,FILE(IN1),DATASET('USR.N123.AB.SASDATA'),SHR ALLOC FI(lNl) DA('USR.N123.AB.SASDATA') SHR ALLOCATE DDNAME(lN1) DATASET('USR.N123.AB.SASDATA') SHR These commands are equivalent and have the same effect as the following JCl statement: IIIN1 DO DSN= USR.N123.AB.SASDATA,DISP= SHR This statement opens a dataset for input. In PC SAS this function is performed by the FILENAME and L1BNAME statements. TSO commands need not be in uppercase. If you want to create a file you can use any of the forms given above. For example: ALLOC FI(OUT1) DA('USR.N123.AB.HEALTH.EXPENSES') SPACE(10 5) TRACKS NEW CATALOG RELEASE This command creates a 10 track file on disk with the option of getting 5 more tracks if the initial 10 tracks are used up. It releases any unused space when you free the dataset or log off. The format for freeing a dataset during a TSO session is: FREE FI(OUT1) DA('USR.N123.AB.HEALTH.EXPENSES') You now have enough information to upload/download a SAS dataset. Only one detail remains: TSO commands submitted from within a SAS program must be preceded by an X. For further information see the SAS COMPANION FOR THE MVS ENVIRONMENT (or SAS COMPANION FOR THE CMS ENVIRONMENT and/or any general text about TSO, e.g. Doug Lowe (1990) MVS TSO. PROC DOWNLOAD This procedure is used to transfer SAS datasets from the host computer to your PC. Example: 242

5 X ALLOC FI(lN1) DA('USR.N123.AB.SASDATA') SHR ; PROC DOWNLOAD DATA=IN1.SASDATA OUT=TEMP; Submit this program to the host computer with the RSUBMIT command. At the end of the job a temporary dataset named TEMP.SSD is created in the SASWORK directory of the Pc. If you want to save this dataset directly on your disk as a permanent SAS dataset, be sure to issue a LlBNAME statement before starting to download. In this case the OUT= parameter points to a two (2) level name e.g. OUT1.SASDATA, where the first part is the libref as usual. PROC UPLOAD This procedure is used to transfer SAS datasets to the host computer from your Pc. example: X ALLOC FI(OUT1) DA('USR.N123.AB.SASDAT2') SPACE(10 5) TRACKS NEW CATALOG RELEASE; PROC UPLOAD DATA=TEMP2 OUT=OUT1.SASDAT2; Submit this program to the host computer with the RSUBMIT command. If the dataset you want to upload is on a disk, be sure to issue a LIB NAME statement before starting to upload. In this case the DATA= parameter points to a two (2) level name e.g. IN1.SASDAT2, where the first part is the libref as usual. Remember to SIGNOFF (close RLlNK) and to log off from TSO at the end of your session. Note that the SIGNOFF command does not log you off from TSO. Your account is charged just for the privilege of being connected to TSO even if you do absolutely nothing. REMOTE SUBMISSION OF A SAS JOB. Sometimes a PC lacks the horsepower to perform a given analysis. If so, you can have the PC "remote submit" the job to mainframe SAS and have the results sent back to your Pc. Remember to submit with the RSUBMIT command. For this to work, the dataset(s) to be processed must be either on the mainframe or in the SASWORK directory on your Pc. Your program can be either on the mainframe or the Pc. If it is on the mainframe it should be stored in fixed block format. Any ICL should be replaced by approriate TSO commands. Use the %INCLUDE statement to access that program. The usage of this statement is explained in both the SAS Language Guide and SAS Users Guide: Basics. A sample program follows below: X ALLOC FI(lN1) DA('USR.N123.AB.HEALTH.DATAFILE') SHR ; X ALLOC FI(OUT1) DA('USR.N123.AB.SASDATA') SPACE(10 5) TRACKS NEW CATALOG RELEASE; DATA OUT1.SASDATA; IN FILE IN1 MISSOVER ; INPUT AGE GENDER $ HEIGHT WEIGHT PULSE JUMPS SITUPS ; RATIO = PULSE/JUMPS; This example shows you how to read an ASCII file (i.e. a "flat file") called HEALTH.DATAFILE on your WYLBUR (MVS) account and create a permanent SAS dataset called SASDAT A on disk. Any excess space is released when you log off or issue a FREE command. This job is submitted to the mainframe with the RSUBMIT command. TSO COMMANDS You may obtain more information on any TSO command by typing HELP command at the READY prompt. A basic set of commands follows: ALLOCATE, ATTRIB, CANCEL, DELETE, EDIT, END, EXEC, FREE, LlSTALC, HELP, LlSTCAT, LlSTDS, LOGOFF, LOGON, OUTPUT, PROFILE, RENAME, STATUS & SUBMIT. 243

6 A brief description of the functions of some the above commands follows; ATTRIB CANCEL DELETE EDIT LlSTALC LlSTCAT LlSTDS OUTPUT PROFILE RENAME STATUS allows DCB parameters to be dynamically introduced and named for use with a subsequent ALLOCATE command. stops the processing of a batch job. deletes one or more datasets or members of a partitioned data set (PDS). creates and/or modifies a sequential dataset or a member of of a PDS. This command has several subcommands (or operands). displays information about all datasets and attribute lists associated with your TSO session. equivalent to the WYLBUR command SHOW CAT. displays DCB parameters of a dataset. allows you to view the output of a batch job at your terminal before printing it. used to specify certain user characteristics that control the flow of information to and from your terminal. same function as DOS or WYLBUR command with the same name. equivalent to the WYLBUR command LOCATE. The main reference for this handout is SAS GUIDE to the MICRO-TO-HOST LINK which contains a helpful glossary. Chapters 3-5, 7-9, 11 and appendix 2 are especially informative. Ressler and Whittle (1990) is an excellent paper that gives an ovelview of the intricacies of file transfer. Painter (1989) has some tips on how to write portable SAS code. Be sure to read the section entitled COMMON MISTAKES in this handout. TRANSPORTING SAS DATASETS ON A NETWORK Networks offer an alternative to the Micro-to-Host link described above. 5AS datasets can be transported over networks, e.g. BITNET, like any other file. If you use a network, it must transfer the file in BINARY format. Further, SAS datasets to be transferred on networks must be prepared in a specific way. The SAS dataset must be converted into transport format using PROC XCOPV with the EXPORT option on the mainframe before file transfer starts. A SAS dataset in transport format is a (physical) sequential file whose DCBs are; RECFM= FB, LRECL= 80 and BLKSIZE= That is, records must be of fixed length (80 characters), blocked with 8000 characters per block. This is achieved by issuing the following KERMIT commands on the mainframe before commencing file transfer: SET FILE LRECL 80 SET FILE BLKSIZE 8000 SET FILE RECFM F SET FILE TYPE BINARY Each command is followed by a carriage return. If you are using another package be sure to consult the manual for equivalent commands. For example, if you have access to TCP/IP you may use FTP (File Transfer Protocol) on TSO. Type in HELP LOCSITE after invoking FTP. Pay close attention to the parameters RECfm, BLocksize, LRed, DCbdsn, PRimary, SECondary and TRacks. In the FTP environment, the LOCSITE command enables you to allocate space for your file and to define its DCB characteristics or to use the DCB attributes of another file. Remember to transfer your file in BINARY format. The format of the commands is as follows; LOCSITE LRECL = 80 LOCSITE BLKSIZE = 8000 LOCSITE RECFM= FB BINARY Each command is followed by a carriage return. Note; the LOCSITE command may not be available on operating systems other than TSO (MVS). To read a version 5 SAS dataset in transport format on a PC, you need to use the SASV5XPT engine that is provided with SAS 6.04 to convert it to version 6 format. The syntax is as follows: 244

7 L1BNAME INl SASV5XPT 'C:\MYSAS\SASFILE.DAT' ; L1BNAME OUT1 'C:\MYSAS' ; PROC COpy IN=INl OUT=OUTl i This piece of code takes a version 5 SAS dataset in transport format named SASFILE.DAT and converts it to a version 6 SAS dataset named SASFILE.SSD (if and only if, SASFILE was the name you used on the mainframe when you created the SAS dataset) in the directory MYSAS on the Pc. In this operation, it is important to use a fully qualified filename in the L1BNAME statement that points to the source of the SAS transport file. Note: If you are writing the transport file to tape, the tape must be UNLABELED (NL), and there should be only ONE transport file per tape. The transport file can be a library of SAS datasets. Chapter 15 of the SAS Language Guide for Personal Computers Release 6.03 discusses the structure of SAS files. Chapter 55 of the SAS User's Guide: Basics, Version 5 Edition gives explicit details on how transport SAS datasets should be prepared on the mainframe using PROC XCOPY. EXPORTING A VERSION 6 SAS DATASET TO VERSION 5.18 You can export a SAS dataset from your PC (6.04) to the mainframe (5.18) using a network like BITNET instead of the Micro-to-Host Link. That SAS dataset must first be converted to transport format using the SASV5XPT engine on the PC and PROC COPY. Note that PROC CPORT is used to prepare transport dataset to other Version 6 systems. Suppose you have a SAS dataset created on the PC with release 6.04 called SASDATA.5SD that you want to export to a mainframe running release The following piece of code creates a transport SAS dataset (SASDATA.TRN) that can be transferred over a network using KERMIT. L1BNAME INl 'C:\MYSAS' ; L1BNAME OUT1 SASV5XPT 'C:\MYSAS\SASDATA.TRN' ; PROC COPY IN = INl OUT= oun ; SELECT SASDATA ; Before you receive this file on the mainframe, be sure to issue the KERMIT commands that cause this file to be transferred in binary format and to be stored with the following DCBs: RECFM = FB, LRECL = 80 and BLKSIZE= The appropriate commands have been covered above and are not repeated. Note that it is important to use a fully qualified filename in the L1BNAME statement that points to the destination of the SAS transport file. USING SAS/ASSIST FOR FILE TRANSFER SASIASSIST provides a menu-driven interface to the Micro-to Host Link for transporting both SAS datasets and other files. The following discussion assumes that you installed SAS/ASSIST and that you have already run the SETUP program for it. Copy the changes you made to the AUTOXEC.SAS file into the ASSIST.SAS file located in the SASMACRO subdirectory. Bring up SAS as usual and issue a LlBNAME statement to indicate the directory that contains the dataset which you wish to upload or the directory where you want to store the dataset that you want to download. At the command line type AF to activate ASSIST. DOWNLOADING Click on the DATA and REMOTE buttons in succession to access the Micro-to-Host Link screen. You will see the following choices: HELP, DEVICE, DEFINE, SIGNON, UPLOAD, DOWNLOAD, SIGNOFF and GOBACK. Click on DEVICE to choose a remote device for the pc and select ASYNC1. for COM1 or ASYNC2 for COM2. If you made the changes to the AUTOEXEC.BAT file as suggested above you need not do this. DEFINE allows you tell ASSIST which script file you need to use. If you made changes to your AUTOEXEC,SAS and/or ASSIST.SAS file as suggested above you need not select repeat this using the DEFINE button. SIGNON allows you to signon onto the host computer to activate SAS on that computer (assuming you are already logged on). DOWNLOAD takes you a screen entitled Download Information to the SIGNOFF and GOBACK. Choose DATASET to go to the Download SAS Dataset to Micro screen where you identify the dataset to be downloaded. At the line Name of Dataset to Download enter the name of a member in a SAS 245

8 library that you want to transfer, e.g. SASDATA. At the line Host System Data library Name enter the fully qualified name of the SAS library, e.g. USR.N123.AB.SASLIB. At the line Name for Downloaded Dataset enter the name that you want to call the downloaded dataset, e.g. OUT1.INCOME. Here, OUT1 is the libref that was issued before invoking ASSIST. After making all these choices press the OK button. After a few seconds SAS will display a bar indicating how much data has been transferred. After 100% data transfer the bar will disappear and nothing will be displayed for a while. At the end of successful data transfer SAS will display the Download SAS Dataset to Micro screen again. If you are done, press the CANCEL button and then the SIGNOFF button. Do not forget to logoff from the host. UPLOADING If you want to upload, you must have a pre-existing SAS library with unused space in which to store the uploaded dataset. Sign on using ASSIST and click on the UPLOAD button. This takes you to a screen entitled Upload Information to Host System. You will see the following choices: HELP, DATASET, FILES, SIGNOFF and GOBACK. Choose DATASET to go to a screen entitled Upload SAS Dataset to Host where you identify the dataset to be uploaded and the SAS library on the host where you want to store it. At the line Name of Dataset to Upload enter the name dataset you want to upload, e.g. IN1.SASDATA where IN1 is the libref issued before invoking ASSIST. At the line Host SAS Data library Name enter the fully qualified name of the SAS library on the host which has unused space, e.g. USR.N123.AB.SASLIB. At the line Filename for Uploaded Dataset enter the member name for the uploaded dataset e.g. FROM604. After making all these choices press the OK button. As in downloading the cursor disappears and for a while it appears as though nothing is happening. After a few seconds SAS will display a bar indicating how much data has been transferred. After 100% data transfer the bar will disappear and nothing will be displayed for a while. At the end of successful data transfer SAS will display the Upload SAS Dataset to Host System screen again. If you are done, press the CANCEL button and then the SIGN OFF button. Do not forget to logoff from the host. PROBLEMS WITH UPLOADING USING SAS/ASSIST. A bug in ASSIST causes an uploaded SAS dataset to be stored in the library with only the first letter as its name, e.g. F. To confirm this do a PROC CO.NTENTS on the SAS dataset where the upoaded file is stored. If you installed ASSIST with the source code and have SAS/AF, you may rectify this. At the command line of the program window type AF C=SASHELP.ASSIST.MACROS.PROGRAM followed by a RETURN. Then edit the L1NKUPDA program by running the following program: PROC BUILD C=SASHELP.ASSIST.lINKUPDA.PROGRAM; At the line Filename for Uploaded Dataset increase the number of underscores after the phrase &FILENAME to seventeen (17). At the command line (which you may find using the HOME key) type COMPILE followed by a RETURN. You may want to change the color of the text before compiling your program by typing COLOR TEXT YELLOW (or whatever color you like), at the command line. Type END at each screen until you back out of AF. COMMON MISTAKES The most common mistake is trying to submit a job to the mainframe that runs against a dataset that is either on a hard or floppy disk before issuing a libname statement. This statement tells SAS where a dataset resides that you want to upload or where to save your file as it is downloaded. If a L1BNAME statement is not issued before starting to download/upload SAS will reply with error messages such as file allocation failed or dataset not found. Otherwise, datasets that you wish to transfer should reside on the mainframe or be created in the current session of PC SAS before starting RLINK. Another common mistake is submitting the job with a SUBMIT command rather than the RSUBMIT command. If the SUBMIT command is used SAS will issue the error message: PROC UPLOAD (or DOWNLOAD) not found. This is because, as just stated above, both PROC DOWNLOAD and PROC UPLOAD reside on the mainframe. 246

9 A frequent mistake when transferring SAS dataset outside of Micro-to-Host Link is failing to transmit the file in BINARY format or failing to use the proper DCBs. This often requires the file to be transferred again which can be time consuming. CONCLUSION This paper has dealt with the implementation of the Micro-to-Host Link in two (2) environments: DOS and MVS at a specific site. It can easily be modified to suit other environments and sites. Once the initial editing of files (AUTOEXEC.BAT, AUTOEXEC.SAS & TSO.SCR or CMS.SCR or VMS.SCR) is done, the Microto-Host Link offers an easy method of transferring SAS datasets (version 5 and 6 of SAS). SAS/ASSIST is a convenient menu driven front-end to the Micro-to-Host Link but requires some debugging in order to work satisfactorily. This debugging requires ASSIST to be loaded with source code as well as the presence of SAS/AF. Uploading SAS datasets with ASSIST requires a pre-existing SAS dataset on the host with unused space in which to store the uploaded file. Networks and telecommunications lines provide an alternative method of transferring SAS datasets electronically, independent of the Micro-to-Host Link. However, this entails an intermediate step of converting the dataset into transport format before file transfer starts. FURTHER INFORMATION Fischell T.R SAS Transport Disk Files: Mainframes, PCs, and Minis. SUGI 16: Ressler, D. and H. Whittle Transporting Files in Release 6.06 of the SAS System. SUGI 15: SAS Institute Inc SAS Companion for the MVS Environment, Version 6. SAS Institute Inc., Cary, NC. Painter S Writing Portable SAS Programs. SUGI 14: SAS Institute Inc SAS Technical Report P-195: Transporting SAS Files between Host Systems. SAS Institute Inc., Cary, NC. SAS Institute Inc SAS Guide to the Micro-to-Host Link. Version 6. SAS Institute Inc., Cary, NC. ACKNOWLEDGEMENTS It is a pleasure to acknowledge the editorial assistance of Helen Aynn of Texas A&M University. Tom Hall, Fran Insley and Yvonne Selby of the SAS Institute greatly assisted me by reading and correcting earlier drafts of this paper, as well as suggesting fixes to SAS/ASSIST. Any errors that remain are entirely mine. 247