I would like to use paste to add new column in original file first.xls.My files:first.xls111second.xls222I'm using:paste -d'\t' first.xls  second.xls >> first.xlsand I getfirst.xls:1111 21 21 2but what I want isfirst.xls:1 21 21 2I don't want to save it to new file I want to overwrite first.xls from beginning.I need this because I want to paste new column to my last results to add new column with every time I run script1 2 21 2 21 2 2then1 2 2 21 2 2 21 2 2 2and so on...
paste and save the result to the 1st argument without using temp files
text processing;paste