A tip related to the VI editor

Often when we receive files by e-mail, we find an unwanted character "^M" (CTRL-M) at several places. This is the control character roughly equivalent of a carriage return. If you use vi, like I do, a natural thing is to try and get rid of this using "global substitution", which is done using:


The above command replaces string "A" by the string "B". So we can use "^M" for "A" and " " (empty space) for "B". But then as soon as we try to type "^M" in place of "A", it is treated as carriage return, and we are back in the file. A way to avoid this is to type "^V" (CTRL-V) before "^M". Thus, to simply remove all the occurances of "^M", use:

:g/^V^M/s// /g

Sometimes, this "^M" appears inadvertantly and makes the entire file as a single line. A solution to that is to replace "^M" by itself! Thus you use:


By the way, all the "V" and "M" when keyed with "CTRL" are actually in lowercase and one doesn't have to use the "SHIFT" or "CAPS LOCK" keys while entering them.

I haven't been able to easily locate these little tips even though there are many sites devoted to "vi" such as:

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