Find file in directory from command line

find /root/directory/to/search -name 'filename.*'
# Directory is optional (defaults to cwd)

Standard UNIX globbing is supported. See man find for more information.

If you're using Vim, you can use:

:e **/filename.cpp

Or :tabn or any Vim command which accepts a filename.

If you're looking to do something with a list of files, you can use find combined with the bash $() construct (better than backticks since it's allowed to nest).

for example, say you're at the top level of your project directory and you want a list of all C files starting with "btree". The command:

find . -type f -name 'btree*.c'

will return a list of them. But this doesn't really help with doing something with them.

So, let's further assume you want to search all those file for the string "ERROR" or edit them all. You can execute one of:

grep ERROR $(find . -type f -name 'btree*.c')
vi $(find . -type f -name 'btree*.c')

to do this.