Regex with grep - match unknown number of alphabetical characters? -

i searching like:

stringone_****_******_stringtwo

where know stringone , stringtwo. * reflect unknown number of letters (capital), however.

i had been under assumption

grep -nr "stringone_\w+_\w+_stringtwo" .

would work, not finding matches.

how can formulate regex correctly (using grep in cygwin)?

have @ manual. without -e flag, grep assumes "basic" regular expressions. in case meta-characters lose special meaning, unless escape them. do

grep -nr "stringone_\w\+_\w\+_stringtwo"

grep -nre "stringone_\w+_\w+_stringtwo"

or, since want uppercase letters:

grep -nr "stringone_[a-z]\+_[a-z]\+_stringtwo" grep -nre "stringone_[a-z]+_[a-z]+_stringtwo"

otherwise, strings 3 or more components in middle accepted.

Naan