The pipeline that you're running is:

Code:

diff ${file1} ${file2} |grep "^<" > ${LOG_path}/LOG${toolnr}.TXT

Please just enter the command:

Code:

diff ASML_LOGBOOK.TXT ASML_LOGBOOK_2.TXT

and look at the output produced. Note that this command is the first command in your pipeline after the shell expands the file1 and file2 variables.
Note that there are lines starting with < which identify lines that are in file2, but not in file1; lines starting with > which identify lines that are in file1, but not in file2; and lines not starting with < or > that indicate where the lines starting with < and > appear in the files. The second stage in your pipeline:

Code:

grep "^<"

says that you want to discard all of the output produced by diff except for the lines that have < as the first character on the line. This means that you are throwing away all of the information that tells you whether the lines you have selected are lines that are different in file1 than they are in file2 or are only present in file2. You are also throwing away all of the information that shows lines that are in file2, but not present in file1; lines that show how a line that changed appears in file2; and lines that were in file1, but are not present in file2; and all of the lines that indicate where lines that were added, deleted, or changed appear in these files.

If this is what you want and you also want to throw away the first two characters (< and space) from the remaining lines, replace the

Code:

grep "^<"

in your pipeline with:

Code:

awk  '!/^</ {next} {sub(/^../,"");print}'