Rexx calls OMVS/USS command to expand JCL with parms

/** rexx vim: set ft=rexx: **/
/*author: Ricky Wu*/
/*function: expand JCL*/

arg jclsrc
jclsrc = strip(jclsrc,,"'")
isredit macro
uid=SYSVAR(SYSUID)

/*check parm*/
if length(jclsrc) = 0 then
do
    address isredit "(dsname) = dataset"
    address isredit "(mbr)    = member"
    jclsrc=dsname || "(" || mbr || ")"
end

/*check Unix System Services*/
if syscalls("ON") <> 0 then
    do
        say "Unix System Services not unavailable"
        exit
    end

address tso "oput "jclsrc" '/tmp/"uid"J'"

"ALLOC F(XXIN) DS('"jclsrc"') SHR REUSE"
"EXECIO * DISKR XXIN (FINIS STEM in."
"FREE F(XXIN)"
/* search from first line to end of file */
do recid = 4 to 6
    startcol = 0
    endcol   = 0
    startcol = pos("=",in.recid,20)
    if startcol <> 0 then
        endcol = pos(" ",in.recid,startcol)
    /*parse lib and member*/
    if startcol <> 0 & endcol <> 0 then 
        do
            if recid = 4 then
                do
                    len = endcol - startcol - 1
                    libFolder = substr(in.recid, startcol + 1, len)
                    /*check for multi lib*/
                    mulCol = pos('(', in.recid, startcol)
                    comCol = pos(',', in.recid, startcol)
                    if mulCol <> 0 then
                        do
                            len = comCol - mulCol - 1
                            libFolder = substr(in.recid, mulCol + 1, len)
                        end
                end
            else
            do
                /*get member name*/
                len = endcol - startcol - 1
                memName = substr(in.recid, startcol + 1, len)
                cmd = 'cat "//'''libFolder"("memName")'"" "
                cmd = cmd || ">> /tmp/ricky"
                call bpxwunix cmd
            end
        end
    else
        do
            if recid = 4 then
                say "Error: = sign not found"
        end
end

/*parse env var.*/
cmd = 'sed -e "\/\/\*/d;s/\/\/ *SET /\&/g;s/=''/\.=/g;s/=\&/\.=\&/g;s/'''
cmd = cmd || ' *$//g;s/ *$//g;" /tmp/ricky' 
cmd = cmd || " > /tmp/parm;"
cmd = cmd || "awk -F= 'BEGIN{ while((getline<""/tmp/parm"")>0)"
cmd = cmd || "{ if ($0~/^\&ENV\./){a[$1]=($2);} }"
cmd = cmd || " close(""/tmp/parm"") } { for(x in a)"
cmd = cmd || "{ if ($0~x){ gsub(x, a[x]); } }"
cmd = cmd || " print$0 }' /tmp/parm > /tmp/env;"
cmd = cmd || "awk -F= 'BEGIN{ while((getline<""/tmp/env"")>0)"
cmd = cmd || "{ if ($0~/^\&.*\./){a[$1]=($2);} }"
cmd = cmd || " close(""/tmp/env"") } { for(x in a){ if ($0~x)"
cmd = cmd || "{ gsub(x, a[x]);} } print$0 }' /tmp/" 
cmd = cmd || uid"J > /tmp/"uid"T"
call bpxwunix cmd

address tso "oget '/tmp/"uid"T' " || uid".TMP."uid"J"
cmd = "rm /tmp/ricky"
call bpxwunix cmd

"ISPEXEC VIEW DATASET('" || uid || ".TMP." || uid || "J') MACRO(RESET)"