find

=====

Format

find [-H] [-L] [-P] [-D debugopts] [-Olevel] [path...] [expression]

Options

-P Never follow symbolic links. Default Behaviors.
-L Follow symbolic links.
-H Don’t follow symbolic links unless it was specified in path

Examples

$ ls -al
total 0
drwxrwxr-x   5 matrix matrix 157 Mar  5 07:40 .
drwxrwxrwt. 10 root    root    197 Mar  5 07:40 ..
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:20 abc
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:20 about.html
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:20 a.log
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:20 a.txt
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:20 axyz.log
-rw-rw-r--   1 matrix matrix   0 Mar  4 20:26 b.html
lrwxrwxrwx   1 matrix matrix   4 Mar  5 07:40 etc -> /etc
lrwxrwxrwx   1 matrix matrix  10 Mar  5 07:36 hosts -> /etc/hosts
drwxrwxr-x   2 matrix matrix  19 Mar  4 20:21 testdir
drwxrwxr-x   2 matrix matrix   6 Mar  4 20:31 testdir1
drwxrwxr-x   2 matrix matrix  22 Mar  4 20:21 xyz

$ find . -name "host*" 2>/dev/null
./hosts

$ find -H . -path './etc/*' -name 'host*' 2>/dev/null | wc -l
0

$ find -H ./etc -path './etc/*' -name 'host*'  2>/dev/null
./etc/host.conf
./etc/hosts
./etc/hosts.allow
./etc/hosts.deny
./etc/cloud/templates/hosts.debian.tmpl
./etc/cloud/templates/hosts.freebsd.tmpl
./etc/cloud/templates/hosts.redhat.tmpl
./etc/cloud/templates/hosts.suse.tmpl
./etc/hostname

$ find -L etc -path 'etc/*' -name 'host*'  2>/dev/null
etc/host.conf
etc/hosts
etc/hosts.allow
etc/hosts.deny
etc/cloud/templates/hosts.debian.tmpl
etc/cloud/templates/hosts.freebsd.tmpl
etc/cloud/templates/hosts.redhat.tmpl
etc/cloud/templates/hosts.suse.tmpl
etc/hostname

-D debugoptions
rates Prints a summary indicating how often each predicate succeeded or failed

-O enable query optimisation

-regextype type
available options: emacs(default), posix-awk, posix-basic, posix-egrep and posix- extended

Expressions

made up of

• options affect overall operation rather than the processing of a specific file, and always return true
• tests return a true or false value
• actions have side effects and return a true or false value and all expressions are connected with operators

Operators

Listed in order of decreasing precedence:

options

• -daystart
  Measure time from the beginning of today rather than from 24 hours ago

• -depth
  Process each directory’s contents before the directory

• -maxdepth level
  Search only at most level (a non-negative integer) levels

• -mindepth level
  Not apply any tests or actions at levels less than level (a non-negative integer). 1 means that all files except the command line arguments

$ date
Sun Mar  5 19:20:25 UTC 2023

$ stat -c'%y %n' /tmp/find/abc
2023-03-04 20:20:40.991547101 +0000 /tmp/find/abc

$ find /tmp/find -daystart -type f -atime -1 -name 'abc' | wc -l
0

$ find /tmp/find  -type f -atime -1 -name 'abc'
/tmp/find/abc

tests

Match time

• -amin n / -cmin n / -mmin n
• -atime n / -ctime n / -mtime n (Unit: days)
• -anewer file / -cnewer file / -newer file
• -newerat TIME / -newerct TIME / -newermt TIME

Note: -mtime -N time range < N days -mtime N time range N <= A < N+1 days -mtime +N time range >= N+1 days

$ stat -c'%y %n' b.html
2023-03-04 20:26:55.897968386 +0000 b.html

$ find . -type f -newerct '2023-03-04 20:25:00 +0000'
./b.html

Match file name

• -iname pattern
  match filename (without path) in case insensitive

• -path pattern / -ipath pattern
  match filename (with path)

• -regex pattern / -iregex pattern
  match regular expression pattern

Match permissions / owner / group

• -perm mode
  exactly match mode

• -perm -mode
  All of the permission bits of mode are set

• -perm /mode
  Any of the permission bits of mode are set

# 640 = 000 110 100 000
$ find . -perm /640 -name a.txt
./a.txt

$ stat -c %a a.txt
400
# 400 = 000 100 000 000

• -readable / -writable / executable

• -uid n / -user uname

• -gid n / -group gname

• -nogroup / -nouser
  match group or owner unable to map to any name

Misc

• -false

• -true

actions

• -print
  print all matching files / dirs with full relative path, and it is default action if no action was specified

• -printf
  print all matching files / dirs with specified format

• -print0
  print all matching files / dirs ended with ‘\0’

• -delete

• -exec command \;

• -ok command \;
  interactively run command for all matching files / dirs

• -prune
  if matching is dir, skip it. If -depth used, matching dir will not be skipped as contents of dir will be processed firstly.

$ find . -name 'a.log'
./a.log
./testdir/a.log

$ find .  -path './testdir' -prune ! -name 'testdir' -o -name 'a.log'
./a.log

$ find . -depth -path './testdir' -prune ! -name 'testdir' -o -name 'a.log'
./a.log
./testdir/a.log

 $ find . -depth -path './testdir' -prune -o -name 'a.log'
./a.log
./testdir/a.log
./testdir