Character classes not working in grep command
Seems grep / egrep does not support character classes, e.g.
# find -type f | grep -e '[\d]'
It finds all the file contains the character d, instead of decimal number(s).
Answer:
By default, egrep only understand the POSIX Basic Regular Expressions (BRE) standard, so what would like to use is:
# find -type f | grep -e '[[:digit:]]'
or you can force to interpret as a Perl regular expression
# find -type f | grep -P -e '[\d]'
