You don't want to do this inline, unless you can ensure that the lines are exactly the same length, or you will overwrite parts of the next line.

One solution: create a lock file.

do {} until (lock_file());
do_work_in_tmp_file();
copy_tmp_file();
unlock_file();

[download]

In reply to Re: Modifying lines of text by MidLifeXis
in thread Modifying lines of text by Anonymous Monk

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