I have a preferences file formatted: 
pref1\t0\n
pref2\t1\n
pref3\t0\n
pref4\t1\n

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What code would I use to search for the line starting with $a (pref1, pref2... etc) and change the single digit following it to another single digit. I do not want to have to rewrite the entire file because it may be quite long.

thanks
z

In reply to How can I replace a single character (digit) in a file by sofreshsoclean

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