Hi, I will have to split a 4 MB file into four 1 MB files. But the problem here is the first line is a header and the last line is a trailer. In between I have second level header which can repeat (2HDR) and under each 2HDR there can be any number of other lines and a second level trailer (2TRL).When the file is split, and one 2HDR should have its 2TRL in the same file. One set can be as small as 200KB and as big as 1 MB. sample file HDR 2HDR ........... .......... ......... 2TRL 2HDR ......... ......... ........ 2TRL 2HDR ......... 2TRL TRL Thanks in advance.

A way ... But whatever method you choose, it will probably take a while. I'm assuming you want the HDR and TRL lines removed. This will break datafile into splitfile.1, splitfile.2 and splitfile.3. Change the filename when you find a line starting with 2HDR. #!/bin/ksh rm -f splitfile.* fbase="splitfile" cnt=0 while read line do case $line in HDR|TRL) continue ;; 2HDR*) ((cnt+=1)) ff="${fbase}.${cnt}" ;; esac echo "$line" >> $ff done < datafile

Thanks a million. It worked.