`find` - search for files in a directory hierarchy

find [path...] [expression]

Options you will use

-name PATTERN: Match the base name against a shell glob. Quote it!
-iname PATTERN: Case-insensitive -name.
-type [fdl]: f regular file, d directory, l symlink.
-size +N[ckMG]: Size greater than N (- for smaller). -size +1G.
-mtime +N / -N: Modified more than / less than N*24 hours ago.
-mmin +N / -N: Modified more / less than N minutes ago.
-perm -MODE: All of these permission bits set. -perm -4000 finds setuid binaries.
-user NAME, -group NAME: Owned by a user or group.
-maxdepth N, -mindepth N: Limit the descent. Put these BEFORE other tests.
-empty: Empty file or directory.
-path PATTERN, -not, -o, -a, ( ): Path match, negation, or, and, grouping.
-print, -printf FORMAT: Print the name, or a custom format (%p path, %s size, %m octal mode, %u user).
-delete: Delete matching files. Test with -print FIRST.
-exec cmd {} ;: Run cmd once per file. With + instead of ; batch many files per run.
-L: Follow symbolic links (look at what they point to).
-xdev: Do not descend into directories on other file systems (other mounts).
-nouser: Files whose owner UID has no user name (a deleted user).
-nogroup: Files whose group GID has no group name.
-print0: Print the name followed by a NUL byte instead of a newline: safe with spaces, pairs with xargs -0.
-xtype TYPE: Like -type, but for a symlink tests what it points to; -xtype l finds broken links.

$ find /data -size +1G -type f

the space hogs

$ sudo find /srv/cache/sessions -type f -mtime +7 -delete

survives "Argument list too long" where rm * does not

$ find . -type d -empty -not -path './.git*' -exec touch {}/.gitkeep ;

make empty dirs visible to git

$ find /usr/bin -perm -4000 -type f

every setuid binary on the box

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