usr.bin/find/find.1

.\" Copyright (c) 1990 The Regents of the University of California.
.\" All rights reserved.
.\"
.\" %sccs.include.redist.man%
.\"
.\"     @(#)find.1	6.19 (Berkeley) 03/14/91
.\"
.Vx
.Vx
.Dd
.Dt FIND 1
.Os
.Sh NAME
.Nm find
.Nd walk a file hierarchy
.Sh SYNOPSIS
.Nm find
.Op Fl drsx
.Op Ar path
.Ar expression
.Nm find
.Op Fl drsx
.Op Fl f Ar path
.Ar expression
.Sh DESCRIPTION
.Nm Find
recursively descends the directory tree for each
.Ar path
listed, evaluating an
.Ar expression
(composed of the ``primaries'' and ``operands'' listed below) in terms
of each file in the tree.
.Pp
The options are as follows:
.Pp
.Tw Ds
.Tp Fl d
The
.Fl d
option causes
.Nm find
to perform a depth\-first traversal, i.e. directories
are visited in post\-order and all entries in a directory will be acted
on before the directory itself.
By default,
.Nm find
visits directories in pre\-order, i.e. before their contents.
Note, the default is
.Ar not
a breadth\-first traversal.
.Tp Fl f
The
.Fl f
option specifies a file hierarchy for
.Nm find
to traverse.
If no
.Fl f
option is specified, the first operand after the options is
expected to be the file hierarchy to be traversed.
.Tp Fl r
The
.Fl r
option permits
.Nm find
to execute the utility specified for the
.Ic exec
and
.Ic ok
primaries from other than the directory where
.Nm find
was executed.
.Nm Find
may then change directories during the file hierarchy walk, meaning
that
.Nm find
can traverse hierarchies with path names longer than those directly
resolvable by the kernel.
This usually results in a performance improvement as well.
.Tp Fl s
The
.Fl s
option causes the file information and file type (see
.Xr stat  2  ) ,
returned for each symbolic link to be those of the file referenced by the
link, not the link itself.
If the referenced file does not exist, the file information and type will
be for the link itself.
.Tp Fl x
The
.Fl x
option prevents
.Nm find
from descending into directories that have a device number different
than that of the file from which the descent began.
.Tp
.Sh PRIMARIES
.Tw Ds
.Tp Cx Ic atime
.Cx \&\ \&
.Ar n
.Cx
True if the difference between the file last access time and the time
.Nm find
was started, rounded up to the next full 24\-hour period, is
.Ar n
24\-hour periods.
.Tp Cx Ic ctime
.Cx \&\ \&
.Ar n
.Cx
True if the difference between the time of last change of file status
information and the time
.Nm find
was started, rounded up to the next full 24\-hour period, is
.Ar n
24\-hour periods.
.Tp Cx Ic exec
.Cx \&\ \&
.Ar utility
.Cx \&\ \&
.Op argument ... ;
.Cx
True if the program named
.Ar utility
returns a zero value as its exit status.
Optional arguments may be passed to the utility.
The expression must be terminated by a semicolon (``;'').
If the string ``{}'' appears anywhere in the utility name or the
arguments it is replaced by the pathname of the current file.
Utility will be executed in the directory from which
.Nm find
was executed.
.Tp Cx Ic fstype
.Cx \&\ \&
.Ar type
.Cx
True if the file is contained in a file system of type
.Ar type .
Currently supported types are ``local'', ``mfs'', ``nfs'', ``pc'' and
``ufs''.
The type ``local'' is not a specific file system type, but matches
any file system physically mounted on the system where the
.Nm find
is being executed.
.Tp Cx Ic group
.Cx \&\ \&
.Ar gname
.Cx
True if the file belongs to the group
.Ar gname  .
If
.Ar gname
is numeric and there is no such group name, then
.Ar gname
is treated as a group id.
.Tp Cx Ic inum
.Cx \&\ \&
.Ar n
.Cx
True if the file has inode number
.Ar n  .
.Tp Cx Ic links
.Cx \&\ \&
.Ar n
.Cx
True if the file has
.Ar n
links.
.Tp Ic ls
This primary always evaluates to true.
The following information for the current file is written to standard output:
its inode number, size in 512\-byte blocks, file permissions, number of hard
links, owner, group, size in bytes, last modification time, and pathname.
If the file is a block or character special file, the major and minor numbers
will be displayed instead of the size in bytes.
If the file is a symbolic link, the pathname of the linked\-to file will be
displayed preceded by ``\->''.
The format is identical to that produced by ``ls \-dgils''.
.Tp Cx Ic mtime
.Cx \&\ \&
.Ar n
.Cx
True if the difference between the file last modification time and the time
.Nm find
was started, rounded up to the next full 24\-hour period, is
.Ar n
24\-hour periods.
.Tp Cx Ic \&ok
.Cx \&\ \&
.Ar utility
.Ws
.Op argument ... ;
.Cx
The
.Ic \&ok
primary is identical to the
.Ic exec
primary with the exception that
.Nm find
requests user affirmation for the execution of the utility by printing
a message to the terminal and reading a response.
If the response is other than ``y'' the command is not executed and the
value of the
.Ar \&ok
expression is false.
.Tp Cx Ic name
.Cx \&\ \&
.Ar pattern
.Cx
True if the last component of the pathname being examined matches
.Ar pattern  .
Special shell pattern matching characters (``['', ``]'', ``*'', and ``?'')
may be used as part of
.Ar pattern  .
These characters may be matched explicitly by escaping them with a
backslash (``\e'').
.Tp Cx Ic newer
.Cx \&\ \&
.Ar file
.Cx
True if the current file has a more recent last modification time than
.Ar file  .
.Tp Ic nouser
True if the file belongs to an unknown user.
.Tp Ic nogroup
True if the file belongs to an unknown group.
.Tp Cx Ic perm
.Cx \&\ \&
.Op Fl
.Ar mode
.Cx
The
.Ar mode
may be either symbolic (see
.Xr chmod  1  )
or an octal number.
If the mode is symbolic, a starting value of zero is assumed and the
mode sets or clears permissions without regard to the process' file mode
creation mask.
If the mode is octal, only bits 07777 of the file's mode bits participate
in the comparison.
If the mode is preceded by a dash (``\-''), this primary evaluates to true
if at least all of the bits in the mode are set in the file's mode bits.
If the mode is not preceded by a dash, this primary evaluates to true if
the bits in the mode exactly match the file's mode bits.
Note, the first character of a symbolic mode may not be a dash (``\-'').
.Tp Ic print
This primary always evaluates to true.
It prints the pathname of the current file to standard output.
The expression is appended to the user specified expression if neither
.Ic exec  ,
.Ic ls ,
or
.Ic \&ok
is specified.
.Tp Ic prune
This primary always evaluates to true.
It causes
.Nm find
to not descend into the current file.
Note, the
.Ic prune
primary has no effect if the
.Op \-d
option was specified.
.Tp Cx Ic size
.Cx \&\ \&
.Ar n
.Op Cm c
.Cx
True if the file's size, rounded up, in 512\-byte blocks is
.Ar n  .
If
.Ar n
is followed by a ``c'', then the primary is true if the
file's size is
.Ar n
bytes.
.Tp Cx Ic type
.Cx \&\ \&
.Ar t
.Cx
True if the file is of the specified type.
Possible file types are as follows:
.Pp
.Df I
.Tw Ds
.Tp Cm b
block special
.Tp Cm c
character special
.Tp Cm d
directory
.Tp Cm f
regular file
.Tp Cm l
symbolic link
.Tp Cm p
FIFO
.Tp Cm s
socket
.Tp
.De
.Pp
.Tp Cx Ic user
.Cx \&\ \&
.Ar uname
.Cx
True if the file belongs to the user
.Ar uname  .
If
.Ar uname
is numeric and there is no such user name, then
.Ar uname
is treated as a user id.
.Tp
.Pp
All primaries which take a numeric argument allow the number to be
preceded by a plus sign (``+'') or a minus sign (``\-'').
A preceding plus sign means ``more than
.Ar n  ' ' ,
a preceding minus sign means ``less than
.Ar n  ' '
and neither means ``exactly
.Ar n  ' ' .
.Sh OPERATORS
The primaries may be combined using the following operators.
The operators are listed in order of decreasing precedence.
.Di L
.Dp Cx Ic \&(
.Ar expression
.Cx \&)
.Cx
This evaluates to true if the parenthesized expression evaluates to
true.
.Pp
.Dp Cx Ic \&!
.Cx \&\ \&
.Ar expression
.Cx
This is the unary NOT operator.
It evaluates to true if the expression is false.
.Pp
.Dp Cx Ar expression
.Cx \&\ \&
.Ic and
.Cx \&\ \&
.Ar expression
.Cx
.Dp Cx Ar expression expression
.Cx
The
.Ic and
operator is the logical AND operator.
As it is implied by the juxtaposition of two expressions it does not
have to be specified.
The expression evaluates to true if both expressions are true.
The second expression is not evaluated if the first expression is false.
.Pp
.Dp Cx Ar expression
.Cx \&\ \&
.Ic or
.Cx \&\ \&
.Ar expression
.Cx
The
.Ic or
operator is the logical OR operator.
The expression evaluates to true if either the first or the second expression
is true.
The second expression is not evaluated if the first expression is true.
.Dp
.Pp
All operands and primaries must be separate arguments to
.Nm find  .
Primaries which themselves take arguments expect each argument
to be a separate argument to
.Nm find  .
.Sh EXAMPLES
.Pp
The following examples are shown as given to the shell:
.Tw findx
.Tp Li find  /  \e!  name  "*.c"  print
Print out a list of all the files whose names do not end in ``.c''.
.Tp Li find  /  newer  ttt  user  wnj  print
Print out a list of all the files owned by user ``wnj'' that are newer
than the file ``ttt''.
.Tp Li find  /  \e!  \e(  newer  ttt  user  wnj  \e)  print
Print out a list of all the files which are not both newer than ``ttt''
and owned by ``wnj''.
.Tp Li find  /  \e(  newer  ttt  or  user wnj  \e)  print
Print out a list of all the files that are either owned by ``wnj'' or
that are newer than ``ttt''.
.Tp
.Sh SEE ALSO
.Xr chmod 1 ,
.Xr sh 1 ,
.Xr test 1 ,
.Xr stat 2 ,
.Xr umask 2 ,
.Xr getpwent 3 ,
.Xr getgrent 3 ,
.Xr strmode 3
.Sh STANDARDS
The
.Nm find
utility syntax is a replacement for the syntax specified by the POSIX
1003.2 standard.
The standard syntax is also supported; see the COMPATIBILITY section
below for details.
.Pp
The
.Fl s
option as well as the primaries
.Ic inum
and
.Ic ls
are extensions to the POSIX standard.
.Sh COMPATIBILITY
The traditional, and standardized, syntax for
.Nm find
is as follows.
All of the primaries are preceded by a dash (``\-''), i.e. the
primary ``group'' is specified as ``\-group''.
The
.Fl d  ,
.Fl s ,
and
.Fl x
options are implemented using the primaries ``\-depth'', ``\-follow'',
and ``\-xdev''.
These primaries always evaluate to true.
The operator ``or'' is implemented as ``\-o'', and the operator
``and'' is implemented as ``\-a''.
The set of file trees to be traversed are specified as the first operands
to
.Nm find  .
The first operand beginning with a dash (``\-''), exclamation point (``!'')
or left parenthesis (``('') is assumed to be the beginning of the expression
and the end of the files to be traversed.
.Pp
The
.Nm find
syntax was changed for two reasons.
The first is that the ``\-depth'', ``\-follow'' and ``\-xdev'' primaries
are really global variables that take effect before the traversal begins.
This causes some legal expressions to have unexpected results.
An example is the expression ``\-print \-o \-depth''.
As \-print always evaluates to true, the standard order of evaluation
implies that \-depth would never be evaluated.
This is not the case.
.Pp
The second reason is that traversing file trees with names beginning with
a dash, exclamation point or left parenthesis was impossible.
.Pp
Historic implementations of the
.Ic exec
and
.Ic ok
primaries did not replace the string ``{}'' in the utility name or the
utility arguments unless it appeared without any other characters.
This version replaces it no matter where in the utility name or arguments
it appears.
.Sh BUGS
The special characters used by
.Nm find
are also special characters to many shell programs.
In particular, the characters ``*'', ``['', ``]'', ``?'', ``('', ``)'',
``!'', ``\e'' and ``;'' may have to be escaped from the shell.