Shell Programming and Scripting

awk 'BEGIN {FS="|";OFS=FS;fmt="%s%s"; aOK=bOK=needa=needb=1}

        function prt (X) {for (i=1;i<=7;i++) printf fmt, X[i],OFS; print appch}

        {
         while (aOK || bOK)
                {if (needa) aOK=getline a<filea;
                 if (needb) bOK=getline b<fileb;
                 if (!(aOK||bOK)) exit;
                 if (a==b)                              {needa=1; needb=1; next};

                 if (aOK) {split(a,ai)} else {ai[3]=ai[5]="z"};
                 if (bOK) {split(b,bi)} else {bi[3]=bi[5]="z"};

                 if(ai[3]ai[5]==bi[3]bi[5])             {needa=1; needb=1; appch="u"}
                 else   if(ai[3]ai[5]>bi[3]bi[5])       {needa=0; needb=1; appch="d"}
                        else                            {needa=1; needb=0; appch="i"}

                 if (appch=="d") {prt(bi)} else {prt(ai)};
                }
         exit
        }
        ' filea=new fileb=old new

b|dm|2|bp|20|$lwa!|sdf|u
c|co|3|mb|30|&dhf!|gfh|d
d|te|4|value|40|@kdk-|kdd|u
f|sv|5|jdjd|50|^ghd2|uyy|i