Find

NAME

       find - search for files in a directory hierarchy

SYNOPSIS

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

DESCRIPTION

       This  manual  page  documents  the  GNU version of find.  GNU find searches the directory tree rooted at each given starting-point by evaluating the

       given expression from left to right, according to the rules of precedence (see section OPERATORS), until the outcome is known (the left hand side is

       false for and operations, true for or), at which point find moves on to the next file name.  If no starting-point is specified, `.' is assumed.

       If  you  are  using  find  in an environment where security is important (for example if you are using it to search directories that are writable by

       other users), you should read the `Security Considerations' chapter of the findutils documentation, which is called Finding  Files  and  comes  with

       findutils.   That document also includes a lot more detail and discussion than this manual page, so you may find it a more useful source of informa‐

       tion.

OPTIONS

       The -H, -L and -P options control the treatment of symbolic links.  Command-line arguments following these are taken to be names of files or  direc‐

       tories  to  be  examined,  up to the first argument that begins with `-', or the argument `(' or `!'.  That argument and any following arguments are

       taken to be the expression describing what is to be searched for.  If no paths are given, the current directory is used.  If no expression is given,

       the expression -print is used (but you should probably consider using -print0 instead, anyway).

       This  manual page talks about `options' within the expression list.  These options control the behaviour of find but are specified immediately after

       the last path name.  The five `real' options -H, -L, -P, -D and -O must appear before the first path name, if at all.  A double dash -- could  theo‐

       retically  be  used  to signal that any remaining arguments are not options, but this does not really work due to the way find determines the end of

       the following path arguments: it does that by reading until an expression argument comes (which also starts with a `-').  Now, if  a  path  argument

       would start with a `-', then find would treat it as expression argument instead.  Thus, to ensure that all start points are taken as such, and espe‐

       cially to prevent that wildcard patterns expanded by the calling shell are not mistakenly treated as expression arguments, it is generally safer  to

       prefix wildcards or dubious path names with either `./' or to use absolute path names starting with '/'.

       -P     Never  follow  symbolic  links.  This is the default behaviour.  When find examines or prints information about files, and the file is a sym‐

              bolic link, the information used shall be taken from the properties of the symbolic link itself.

       -L     Follow symbolic links.  When find examines or prints information about files, the information used shall be taken from the properties of  the

              file  to  which the link points, not from the link itself (unless it is a broken symbolic link or find is unable to examine the file to which

              the link points).  Use of this option implies -noleaf.  If you later use the -P option, -noleaf will still be in effect.  If -L is in  effect

              and find discovers a symbolic link to a subdirectory during its search, the subdirectory pointed to by the symbolic link will be searched.

              When  the  -L  option  is in effect, the -type predicate will always match against the type of the file that a symbolic link points to rather

              than the link itself (unless the symbolic link is broken).  Actions that can cause symbolic links to become broken while  find  is  executing

              (for example -delete) can give rise to confusing behaviour.  Using -L causes the -lname and -ilname predicates always to return false.

       -H     Do  not follow symbolic links, except while processing the command line arguments.  When find examines or prints information about files, the

              information used shall be taken from the properties of the symbolic link itself.  The only exception to this behaviour is when a file  speci‐

              fied  on  the command line is a symbolic link, and the link can be resolved.  For that situation, the information used is taken from whatever

              the link points to (that is, the link is followed).  The information about the link itself is used as a fallback if the file  pointed  to  by

              the  symbolic  link cannot be examined.  If -H is in effect and one of the paths specified on the command line is a symbolic link to a direc‐

              tory, the contents of that directory will be examined (though of course -maxdepth 0 would prevent this).

If more than one of -H, -L and -P is specified, each overrides the others; the last one appearing on the command line takes effect.  Since it is the

       default, the -P option should be considered to be in effect unless either -H or -L is specified.

       GNU  find  frequently  stats  files during the processing of the command line itself, before any searching has begun.  These options also affect how

       those arguments are processed.  Specifically, there are a number of tests that compare files listed on the command line against a file we  are  cur‐

       rently  considering.   In each case, the file specified on the command line will have been examined and some of its properties will have been saved.

       If the named file is in fact a symbolic link, and the -P option is in effect (or if neither -H nor -L were specified), the information used for  the

       comparison  will be taken from the properties of the symbolic link.  Otherwise, it will be taken from the properties of the file the link points to.

       If find cannot follow the link (for example because it has insufficient privileges or the link points to a nonexistent file) the properties  of  the

       link itself will be used.

       When  the  -H or -L options are in effect, any symbolic links listed as the argument of -newer will be dereferenced, and the timestamp will be taken

       from the file to which the symbolic link points.  The same consideration applies to -newerXY, -anewer and -cnewer.

       The -follow option has a similar effect to -L, though it takes effect at the point where it appears (that is, if -L is not used but -follow is,  any

       symbolic links appearing after -follow on the command line will be dereferenced, and those before it will not).

       -D debugopts

              Print  diagnostic  information; this can be helpful to diagnose problems with why find is not doing what you want.  The list of debug options

              should be comma separated.  Compatibility of the debug options is not guaranteed between releases of findutils.  For a complete list of valid

              debug options, see the output of find -D help.  Valid debug options include

              exec   Show diagnostic information relating to -exec, -execdir, -ok and -okdir

              opt    Prints diagnostic information relating to the optimisation of the expression tree; see the -O option.

              rates  Prints a summary indicating how often each predicate succeeded or failed.

              search Navigate the directory tree verbosely.

              stat   Print messages as files are examined with the stat and lstat system calls.  The find program tries to minimise such calls.

              tree   Show the expression tree in its original and optimised form.

              all    Enable all of the other debug options (but help).

              help   Explain the debugging options.

-Olevel

Enables  query  optimisation.  The find program reorders tests to speed up execution while preserving the overall effect; that is, predicates  with side effects are not reordered relative to each other.  The optimisations performed at each optimisation level are as follows.

0      Equivalent to optimisation level 1.

1      This is the default optimisation level and corresponds to the traditional behaviour.  Expressions are reordered so  that  tests  based only on the names of files (for example -name and -regex) are performed first.

2      Any  -type  or -xtype tests are performed after any tests based only on the names of files, but before any tests that require information from the inode.  On many modern versions of Unix, file types are returned by readdir() and so  these  predicates  are  faster  to evaluate  than  predicates  which need to stat the file first.  If you use the -fstype FOO predicate and specify a filesystem type FOO which is not known (that is, present in `/etc/mtab') at the time find starts, that predicate is equivalent to -false.

3      At this optimisation level, the full cost-based query optimiser is enabled.  The order of tests is modified so that cheap (i.e.  fast)  tests  are performed first and more expensive ones are performed later, if necessary.  Within each cost band, predicates are evaluated earlier or later according to whether they are likely to succeed or not.  For -o, predicates which are likely to succeed are evaluated earlier, and for -a, predicates which are likely to fail are evaluated earlier.

   The  cost-based  optimiser  has  a fixed idea of how likely any given test is to succeed.  In some cases the probability takes account of the specific nature of the test (for example, -type f is assumed to be more likely to succeed than -type c).  The cost-based  optimiser  is  currently  being  evaluated.  If it does not actually improve the performance of find, it will be removed again.  Conversely, optimisations that prove to be reliable, robust and effective may be enabled at lower optimisation levels over time.  However, the default behaviour (i.e. optimisation  level 1) will not be changed in the 4.3.x release series.  The findutils test suite runs all the tests on find at each optimisation level and ensures that the result is the same.

EXPRESSION

The part of the command line after the list of starting points is the expression.  This is a kind of query specification  describing  how  we  match files and what we do with the files that were matched.  An expression is composed of a sequence of things: Tests  Tests  return a true or false value, usually on the basis of some property of a file we are considering.  The -empty test for example is true  only when the current file is empty.

Actions

Actions have side effects (such as printing something on the standard output) and return either true or false, usually based  on  whether  or not they are successful.  The -print action for example prints the name of the current file on the standard output.

Global options

Global  options affect the operation of tests and actions specified on any part of the command line.  Global options always return true.  The depth option for example makes find traverse the file system in a depth-first order. Positional options Positional options affect only tests or actions which follow them.  Positional options always return true.  The -regextype option for example is positional, specifying the regular expression dialect for regular expressions occurring later on the command line.

Operators

Operators  join  together  the  other  items within the expression.  They include for example -o (meaning logical OR) and -a (meaning logical AND).  Where an operator is missing, -a is assumed.

The -print action is performed on all files for which the whole expression is true, unless it contains an action other than -prune  or  -quit. 

Actions which inhibit the default -print are -delete, -exec, -execdir, -ok, -okdir, -fls, -print, -fprintf, -ls, -print and -printf. The -delete action also acts like an option (since it implies -depth).

POSITIONAL OPTIONS

       Positional options always return true.  They affect only tests occurring later on the command line.

-daystart

Measure  times  (for -amin, -atime, -cmin, -ctime, -mmin, and -mtime) from the beginning of today rather than from 24 hours ago.  This option only affects tests which appear later on the command line.

-follow

Deprecated; use the -L option instead.  Dereference symbolic links.  Implies -noleaf.  The -follow option affects only those tests which  appear  after  it on the command line.  Unless the -H or -L option has been specified, the position of the -follow option changes the behaviour  of the -newer predicate; any files listed as the argument of -newer will be dereferenced if they are symbolic links.  The same  consideration applies to -newerXY, -anewer and -cnewer.  Similarly, the -type predicate will always match against the type of the file that a symbolic link points to rather than the link itself.  Using -follow causes the -lname and -ilname predicates always to return false.

-regextype type

Changes the regular expression syntax understood by -regex and -iregex tests which occur later on the command line.  To see which regular expression  types are known, use -regextype help.  The Texinfo documentation (see SEE ALSO) explains the meaning of and differences between the various types of regular expression.

-warn, -nowarn

Turn warning messages on or off.  These warnings apply only to the command line usage, not to any conditions that find might  encounter  when it searches directories.  The default behaviour corresponds to -warn if standard input is a tty, and to -nowarn otherwise.  If a warning message relating to command-line usage is produced, the exit status of find is not affected.  If the  POSIXLY_CORRECT  environment  variable  is  set, and -warn is also used, it is not specified which, if any, warnings will be active.

  GLOBAL OPTIONS

       Global options always return true.  Global options take effect even for tests which occur earlier on the command line.  To prevent confusion, global

       options should specified on the command-line after the list of start points, just before the first test, positional option or action.  If you  spec‐

       ify a global option in some other place, find will issue a warning message explaining that this can be confusing.

       The global options occur after the list of start points, and so are not the same kind of option as -L, for example.

       -d     A synonym for -depth, for compatibility with FreeBSD, NetBSD, MacOS X and OpenBSD.

       -depth Process each directory's contents before the directory itself.  The -delete action also implies -depth.

       -help, --help

              Print a summary of the command-line usage of find and exit.

       -ignore_readdir_race

              Normally,  find will emit an error message when it fails to stat a file.  If you give this option and a file is deleted between the time find

              reads the name of the file from the directory and the time it tries to stat the file, no error message will be issued.  This also applies  to

              files  or  directories whose names are given on the command line.  This option takes effect at the time the command line is read, which means

              that you cannot search one part of the filesystem with this option on and part of it with this option off (if you need to do that,  you  will

              need to issue two find commands instead, one with the option and one without it).

              Furthermore,  find  with  the -ignore_readdir_race option will ignore errors of the -delete action in the case the file has disappeared since

              the parent directory was read: it will not output an error diagnostic, and the return code of the -delete action will be true.

       -maxdepth levels

              Descend at most levels (a non-negative integer) levels of directories below the starting-points.  Using  -maxdepth 0  means  only  apply  the

              tests and actions to the starting-points themselves.

       -mindepth levels

              Do  not apply any tests or actions at levels less than levels (a non-negative integer).  Using -mindepth 1 means process all files except the

              starting-points.

       -mount Don't descend directories on other filesystems.  An alternate name for -xdev, for compatibility with some other versions of find.

       -noignore_readdir_race

              Turns off the effect of -ignore_readdir_race.

       -noleaf

Do not optimize by assuming that directories contain 2 fewer subdirectories than their hard link count.  This option is needed when searching  filesystems that do not follow the Unix directory-link convention, such as CD-ROM or MS-DOS filesystems or AFS volume mount points.  Each directory on a normal Unix filesystem has at least 2 hard links: its name and its `.' entry.  Additionally, its subdirectories  (if  any)  each have  a `..' entry linked to that directory.  When find is examining a directory, after it has statted 2 fewer subdirectories than the directory's link count, it knows that the rest of the entries in the directory are non-directories (`leaf' files in the directory tree).  If  only the files' names need to be examined, there is no need to stat them; this gives a significant increase in search speed.

-version, --version

              Print the find version number and exit.

-xdev  Don't descend directories on other filesystems.

TESTS

Some  tests, for example -newerXY and -samefile, allow comparison between the file currently being examined and some reference file specified on the command line.  When these tests are used, the interpretation of the reference file is determined by the options -H, -L and -P and any previous -fol‐ low,  but  the reference file is only examined once, at the time the command line is parsed.  If the reference file cannot be examined (for example,  the stat(2) system call fails for it), an error message is issued, and find exits with a nonzero status.

       A numeric argument n can be specified to tests (like -amin, -mtime, -gid, -inum, -links, -size, -uid and -used) as

       +n     for greater than n,

       -n     for less than n,

       n      for exactly n.

       Supported tests:

       -amin n

              File was last accessed less than, more than or exactly n minutes ago.

       -anewer reference

              Time of the last access of the current file is more recent than that of the last data modification of the reference file.  If reference is  a

              symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to is always

              used.

       -atime n

              File was last accessed less than, more than or exactly n*24 hours ago.  When find figures out how many 24-hour periods ago the file was  last

              accessed, any fractional part is ignored, so to match -atime +1, a file has to have been accessed at least two days ago.

       -cmin n

              File's status was last changed less than, more than or exactly n minutes ago.

       -cnewer reference

              Time  of  the last status change of the current file is more recent than that of the last data modification of the reference file.  If refer‐

              ence is a symbolic link and the -H option or the -L option is in effect, then the time of the last data modification of the file it points to

              is always used.

       -ctime n

              File's  status  was  last changed less than, more than or exactly n*24 hours ago.  See the comments for -atime to understand how rounding af‐

              fects the interpretation of file status change times.

       -empty File is empty and is either a regular file or a directory.

       -executable

              Matches files which are executable and directories which are searchable (in a file name resolution sense) by the current  user.   This  takes

              into  account access control lists and other permissions artefacts which the -perm test ignores.  This test makes use of the access(2) system

              call, and so can be fooled by NFS servers which do UID mapping (or root-squashing), since many systems implement access(2)  in  the  client's

              kernel  and  so  cannot make use of the UID mapping information held on the server.  Because this test is based only on the result of the ac‐

              cess(2) system call, there is no guarantee that a file for which this test succeeds can actually be executed.