I would expect the same output of the following two commands, but the first one looks wrong to me:
By the way,
Code:
% echo abc^ABC.123 | sed 's/[^A-z0-9]/_/g' abc^ABC_123 % echo abc^ABC.123 | sed 's/[^[:alnum:]]/_/g' abc_ABC_123
gsed
does the same. Am I missing something?..