mm-subst-char-in-string

mm-subst-char-in-string is an alias for `subst-char-in-string' in `mm-util.el'.

(mm-subst-char-in-string FROMCHAR TOCHAR STRING &optional INPLACE)

Replace FROMCHAR with TOCHAR in STRING each time it occurs.
Unless optional argument INPLACE is non-nil, return a new string.