[linux] How can I find a specific file from a Linux terminal?

Solution: Use unix command find

The find utility recursively descends the directory tree for each path listed, evaluating an expression (composed of the 'primaries' and 'operands') in terms of each file in the tree.

• You can make the find action be more efficient and smart by controlling it with regular expressions queries, file types, size thresholds, depths dimensions in subtree, groups, ownership, timestamps , modification/creation date and more.
• In addition you can use operators and combine find requests such as or/not/and etc...

The Traditional Formula would be :

find <path> -flag <valueOfFlag>

Easy Examples

1.Find by Name - Find all package.json from my current location subtree hierarchy.

find . -name "package.json"

2.Find by Name and Type - find all node_modules directories from ALL file system (starting from root hierarchy )

sudo find / -name "node_modules" -type d

Complex Examples:

More Useful examples which can demonstrate the power of flag options and operators:

3.Regex and File Type - Find all javascript controllers variation names (using regex) javascript Files only in my app location.

find /user/dev/app -name "*contoller-*\.js" -type f

-type f means file -name related to regular expression to any variation of controller string and dash with .js at the end

4.Depth - Find all routes patterns directories in app directory no more than 3 dimensions ( app/../../.. only and no more deeper)

find app -name "*route*" -type d  -maxdepth 3

-type d means directory -name related to regular expression to any variation of route string -maxdepth making the finder focusing on 3 subtree depth and no more <yourSearchlocation>/depth1/depth2/depth3)

5.File Size , Ownership and OR Operator - Find all files with names 'sample' or 'test' under ownership of root user that greater than 1 Mega and less than 5 Mega.

find . \( -name "test" -or -name "sample" \)  -user root -size +1M -size -5M

-size threshold representing the range between more than (+) and less than (-) -user representing the file owner -or operator filters query for both regex matches

6.Empty Files - find all empty directories in file system

find / -type d -empty

7.Time Access, Modification and creation of files - find all files that were created/modified/access in directory in 10 days

# creation (c)
find /test -name "*.groovy" -ctime -10d
# modification (m)
find /test -name "*.java" -mtime -10d
# access (a)
find /test -name "*.js" -atime -10d

8.Modification Size Filter - find all files that were modified exactly between a week ago to 3 weeks ago and less than 500kb and present their sizes as a list

find /test -name "*.java" -mtime -3w -mtime +1w -size -500k | xargs du -h