Easy Printing From CL
March 1, 2016 Ted Holt
CL cannot write to printer files. This is understandable, since CL fits into the category of job control languages. Even though I’d never use CL to build an aged receivables report, there are times when it is advantageous for a CL program to generate a report (i.e., produce a spooled file), and here are two fairly easy ways to do that.
Suppose you have a CL program that runs three RPG programs in nightly batch processing. There are people in your organization who need to know whether these programs ran successfully or not. If you could build a short spooled file with that information, you could route that spooled file to an output queue that is monitored by third-party software, which in turn can email the report in PDF format.
First, create a printer file with the proper settings.
CRTPRTF FILE(MYLIB/STATUSPRTF) + TEXT('Nightly production status report') + OUTQ(EMAILOUTQ)
Here are two ways to build the spooled file.
Method 1: Qshell and Rfile
Make the CL program build a Qshell command that uses the Rfile utility to write to the printer file.
pgm parm(&RunDate) dcl &RunDate *char 8 /* YYYYMMDD */ dcl &Status *char dcl &EOL *char 2 x'0d25' dcl &Cmd *char 256 chgvar &Cmd ('echo ''') call QDP007101R (&RunDate &Status) chgvar &Cmd (&Cmd *tcat 'Widgets =' *cat &Status *cat &EOL) call QDP007102R (&RunDate &Status) chgvar &Cmd (&Cmd *tcat 'Thingies =' *cat &Status *cat &EOL) call QDP007103R (&RunDate &Status) chgvar &Cmd (&Cmd *tcat 'Dohickeys =' *cat &Status *cat &EOL) chgvar &Cmd (&Cmd *tcat ''' | rfile -wQ mylib/StatusPrtf') qsh cmd(&Cmd) endpgm
The &Cmd variable will have a value like this (except that I have put two question marks where the carriage return and line feed characters go):
echo 'Widgets =OK??Thingies =OK??Dohickeys =FAIL??' | rfile -wQ mylib/StatusPrtf
The echo command writes text to the standard output stream. Standard output is piped into the Rfile utility. That is to say, the output from the echo is the input to Rfile. Rfile writes the streamed data to the printer file that we created. Voilà! Several cell phones display the following:
Widgets =OK Thingies =OK Dohickeys =FAIL
Method 2: Native files and RUNSQL
With the exception of the RUNSQL command, this method uses features that have been around since day 1.
pgm parm(&RunDate) dcl &RunDate *char 8 /* YYYYMMDD */ dcl &Status *char dcl &PrintLine *char 24 dcl &Cmd *char 256 dcl &Quote *char 1 value('''') clrpfm qtemp/StatusRpt monmsg cpf3142 exec(do) crtpf qtemp/StatusRpt rcdlen(24) enddo call QDP007101R (&RunDate &Status) chgvar &PrintLine ('Widgets =' *cat &Status) callsubr WriteStat call QDP007102R (&RunDate &Status) chgvar &PrintLine ('Thingies =' *cat &Status) callsubr WriteStat call QDP007103R (&RunDate &Status) chgvar &PrintLine ('Dohickeys =' *cat &Status) callsubr WriteStat cpyf qtemp/statusrpt StatusPrtf fmtopt(*nochk) return subr WriteStat chgvar &Cmd ('insert into qtemp/StatusRpt values(' *cat + &Quote *cat &PrintLine *tcat &Quote *cat ')') runsql sql(&Cmd) commit(*none) endsubr endpgm
This routine begins by clearing program-described work file StatusRpt if it exists and creating it otherwise. After each program call, the WriteStat subroutine writes a record to the work file. The Copy File (CPYF) command copies the work file to the printer file, producing the report.
Where there’s a will, there’s a way.