OpenBSD-4.6/usr.bin/find/find.1

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.\"	from: @(#)find.1	8.1 (Berkeley) 6/6/93
.\"
.Dd $Mdocdate: April 9 2009 $
.Dt FIND 1
.Os
.Sh NAME
.Nm find
.Nd walk a file hierarchy
.Sh SYNOPSIS
.Nm find
.Op Fl dHhLXx
.Op Fl f Ar path
.Ar path ...\&
.Op Ar expression
.Sh DESCRIPTION
.Nm
recursively descends the directory tree for each
.Ar path
listed, evaluating an
.Ar expression
(composed of the
.Dq primaries
and
.Dq operators
listed below) in terms
of each file in the tree.
In the absence of an expression,
.Ic -print
is assumed.
If an expression is given,
but none of the primaries
.Ic -exec ,
.Ic -ls ,
.Ic -ok ,
.Ic -print ,
or
.Ic -print0
are specified, the given expression is effectively replaced by
.Cm \&( Ar given expression Cm \&)
.Ic -print .
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl d
Causes
.Nm
to visit directories in post-order
i.e. all entries in a directory will be acted on before the directory itself.
By default,
.Nm
visits directories in pre-order i.e. before their contents.
.It Fl f Ar path
Specifies a file hierarchy for
.Nm
to traverse.
File hierarchies may be specified without the
.Fl f
option if they are given immediately after any other options.
.It Fl H
Causes the file information and file type (see
.Xr stat 2 )
returned for each symbolic link encountered on the command line 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.
File information of all symbolic links not on
the command line is that of the link itself.
.It Fl h
An alias for the
.Fl L
option.
This option exists for backwards compatibility.
.It Fl L
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.
.It Fl X
Permit
.Nm
to be safely used in conjunction with
.Xr xargs 1 .
If a file name contains any of the delimiting characters used by
.Xr xargs ,
a diagnostic message is displayed on standard error, and the file
is skipped.
The delimiting characters include single
.Pq Ql '
and double
.Pq Ql \&"
quotes, backslash
.Pq Ql \e ,
space, tab, and newline
.Pq Sq \en
characters.
Alternatively, the
.Fl print0
primary may be used in conjunction with the
.Fl 0
option to
.Xr xargs 1 ,
allowing all file names to be processed safely.
.It Fl x
Prevents
.Nm
from descending into directories that have a device number different
than that of the file from which the descent began.
.El
.Sh PRIMARIES
.Bl -tag -width Ds
.It Ic -amin Ar n
True if the difference between the file last access time and the time
.Nm
was started, rounded up to the next full minute, is
.Ar n
minutes.
.It Ic -anewer Ar file
True if the current file has a more recent last access time than
.Ar file .
.It Ic -atime Ar n
True if the difference between the file last access time and the time
.Nm
was started, rounded up to the next full 24-hour period, is
.Ar n
24-hour periods.
.It Ic -cmin Ar n
True if the difference between the time of last change of file status
information and the time
.Nm
was started, rounded up to the next full minute, is
.Ar n
minutes.
.It Ic -cnewer Ar file
True if the current file has a more recent last change time than
.Ar file .
.It Ic -ctime Ar n
True if the difference between the time of last change of file status
information and the time
.Nm
was started, rounded up to the next full 24-hour period, is
.Ar n
24-hour periods.
.It Ic -depth
This primary always evaluates to true.
The same as specifying the
.Fl d
option.
.It Ic -empty
True if the current file or directory is empty.
.It Xo
.Ic -exec Ar utility
.Op argument ...
.No ;
.Xc
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
.Pq Ql \&; .
If the string
.Qq {}
appears anywhere in the utility name or the
arguments it is replaced by the pathname of the current file.
.Ar utility
will be executed from the directory from which
.Nm
was executed.
.Pp
Since
.Ar utility
is executed every time a match is made,
it is often more efficient to pipe the output of
.Nm
to
.Xr xargs 1 .
.It Xo
.Ic -execdir Ar utility
.Op argument ...
.No ;
.Xc
Identical to the
.Ic -exec
primary with the exception that
.Ar utility
will be executed from the directory that holds
the current file.
The filename substituted for the string
.Qq {}
is not qualified.
.It Xo
.Ic -flags
.Oo - Oc Ns Ar flags
.Xc
The
.Ar flags
are comma-separated symbolic file flags (see
.Xr chflags 1
for a list of valid flag names).
If the flags are preceded by a dash
.Pq Sq - ,
this primary evaluates to true if at least all specified
.Ar flags
are set in the file's flags.
If the flags are not preceded by a dash, this primary evaluates to true if the
flags specified exactly match those of the file.
.It Ic -follow
This primary always evaluates to true.
The same as specifying the
.Fl H
option.
.It Ic -fstype Ar type
True if the file is contained in a file system of type
.Ar type .
Two special file system types are recognized:
.Dq local
and
.Dq rdonly .
These do not describe actual file system types;
the former matches any file system physically mounted on the system where
.Nm
is being executed whereas the latter matches any file system which is
mounted read-only.
.It Ic -group Ar gname
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.
.It Ic -iname Ar pattern
True if the last component of the pathname being examined
matches
.Ar pattern .
Case insensitive.
.It Ic -inum Ar n
True if the file has inode number
.Ar n .
.It Ic -links Ar n
True if the file has
.Ar n
links.
.It 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
.Dq -\*(Gt .
The format is identical to that produced by
.Dq ls -dils .
.It Ic -maxdepth Ar n
True if the current search depth is less than or equal to what is specified in
.Ar n .
.It Ic -mindepth Ar n
True if the current search depth is at least what is specified in
.Ar n .
.It Ic -mmin Ar n
True if the difference between the file last modification time and the time
.Nm
was started, rounded up to the next full minute, is
.Ar n
minutes.
.It Ic -mtime Ar n
True if the difference between the file last modification time and the time
.Nm
was started, rounded up to the next full 24-hour period, is
.Ar n
24-hour periods.
.It Ic -name Ar pattern
True if the last component of the pathname being examined matches
.Ar pattern .
Special shell pattern matching characters
.Pf ( Ql [ ,
.Ql \&] ,
.Ql * ,
and
.Ql \&? )
may be used as part of
.Ar pattern .
These characters may be matched explicitly by escaping them with a
backslash
.Pq Ql \e .
.It Ic -newer Ar file
True if the current file has a more recent last modification time than
.Ar file .
.It Ic -nogroup
True if the file belongs to an unknown group.
.It Ic -nouser
True if the file belongs to an unknown user.
.It Xo
.Ic -ok Ar utility
.Op argument ...
.No ;
.Xc
Identical to the
.Ic -exec
primary with the exception that
.Nm
requests user affirmation for the execution of
.Ar utility
by printing
a message to the terminal and reading a response.
If the response is other than
.Sq y
the command is not executed and the
value of the
.Ic ok
expression is false.
.It Ic -path Ar pattern
True if the pathname being examined matches
.Ar pattern .
Special shell pattern matching characters
.Pf ( Ql [ ,
.Ql \&] ,
.Ql * ,
and
.Ql \&? )
may be used as part of
.Ar pattern .
These characters may be matched explicitly by escaping them with a
backslash
.Pq Ql \e .
Slashes
.Pq Ql /
are treated as normal characters and do not have to be
matched explicitly.
.It Xo
.Ic -perm
.Oo - Oc Ns Ar mode
.Xc
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's file mode
creation mask.
If the mode is octal, only bits 07777
.Po
.Dv S_ISUID \*(Ba S_ISGID \*(Ba S_ISTXT \*(Ba
.Dv S_IRWXU \*(Ba S_IRWXG \*(Ba S_IRWXO
.Pc
of the file's mode bits participate
in the comparison.
If the mode is preceded by a dash
.Pq Sq - ,
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.
.It Ic -print
This primary always evaluates to true.
It prints the pathname of the current file to standard output, followed
by a newline
.Pq Ql \en
character.
.It Ic -print0
This primary always evaluates to true.
It prints the pathname of the current file to standard output, followed
by a null character.
.It Ic -prune
This primary always evaluates to true.
It causes
.Nm
to not descend into the current file.
Note, the
.Ic -prune
primary has no effect if the
.Fl d
option was specified.
.It Ic -size Ar n Ns Op Cm c
True if the file's size, rounded up, in 512-byte blocks is
.Ar n .
If
.Ar n
is followed by a
.Sq c ,
then the primary is true if the
file's size is
.Ar n
bytes.
.It Ic -type Ar t
True if the file is of the specified type.
Possible file types are as follows:
.Pp
.Bl -tag -width flag -offset indent -compact
.It Cm b
block special
.It Cm c
character special
.It Cm d
directory
.It Cm f
regular file
.It Cm l
symbolic link
.It Cm p
FIFO
.It Cm s
socket
.El
.Pp
.It Ic -user Ar uname
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.
.It Ic -xdev
This primary always evaluates to true.
The same as specifying the
.Fl x
option.
.El
.Pp
All primaries which take a numeric argument allow the number to be
preceded by a plus sign
.Pq Ql +
or a minus sign
.Pq Ql - .
A preceding plus sign means
.Dq more than n ,
a preceding minus sign means
.Dq less than n ,
and neither means
.Dq exactly n .
Exceptions are the primaries
.Ic mindepth
and
.Ic maxdepth .
.Sh OPERATORS
The primaries may be combined using the following operators.
The operators are listed in order of decreasing precedence.
.Pp
.Bl -tag -width "(expression)" -compact
.It Cm \&( Ar expression Cm \&)
This evaluates to true if the parenthesized expression evaluates to
true.
.Pp
.It Cm \&! Ar expression
This is the unary
.Tn NOT
operator.
It evaluates to true if the expression is false.
.Pp
.It Ar expression Cm -and Ar expression
.It Ar expression expression
The
.Cm -and
operator is the logical
.Tn 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
.It Ar expression Cm -or Ar expression
The
.Cm -or
operator is the logical
.Tn 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.
.El
.Pp
Operators, primaries, and arguments to primaries must be separate
arguments to
.Nm find ,
i.e. they should be separated by whitespace.
.Sh EXAMPLES
Print out a list of all the files whose names end in
.Dq \&.c :
.Pp
.Dl "$ find / -name '*.c'"
.Pp
Print out a list of all the files which are not both newer than
.Dq ttt
and owned by
.Dq wnj :
.Pp
.Dl "$ find / \e! \e( -newer ttt -user wnj \e)"
.Pp
Print out a list of all core files on local file systems:
.Pp
.Dl "$ find / \e! -fstype local -prune -or -name '*.core'"
.Pp
Find all files in
.Pa /usr/src
ending in a dot and single digit, but skip directory
.Pa /usr/src/gnu :
.Pp
.Dl "$ find /usr/src -path /usr/src/gnu -prune -or -name \e*.[0-9]"
.Pp
Find and remove all *.jpg files in the current working directory:
.Pp
.Dl "$ find . -name \e*.jpg -exec rm {} \e;"
or
.Dl "$ find . -name \e*.jpg | xargs rm"
.Sh SEE ALSO
.Xr chflags 1 ,
.Xr chmod 1 ,
.Xr locate 1 ,
.Xr whereis 1 ,
.Xr which 1 ,
.Xr xargs 1 ,
.Xr stat 2 ,
.Xr fts 3 ,
.Xr getgrent 3 ,
.Xr getpwent 3 ,
.Xr strmode 3 ,
.Xr symlink 7
.Sh STANDARDS
The
.Nm
utility is compliant with the
.St -p1003.1-2008
specification.
.Pp
The options
.Op Fl dfhXx
and primaries
.Ic -amin ,
.Ic -anewer ,
.Ic -cmin ,
.Ic -cnewer ,
.Ic -empty ,
.Ic -execdir ,
.Ic -flags ,
.Ic -follow ,
.Ic -fstype ,
.Ic -iname ,
.Ic -inum ,
.Ic -ls ,
.Ic -maxdepth ,
.Ic -mindepth ,
.Ic -mmin ,
and
.Ic -print0
are extensions to that specification.
The
.Ic -iname
primary was inspired by GNU find.
.Pp
Historically, the
.Fl d ,
.Fl H ,
and
.Fl x
options were implemented using the primaries
.Ic -depth ,
.Ic -follow ,
and
.Ic -xdev .
These primaries always evaluated to true.
As they were really global variables that took effect before the traversal
began, some legal expressions could have unexpected results.
An example is the expression
.Dq -print -o -depth .
As
.Cm -print
always evaluates to true, the standard order of evaluation
implies that
.Cm -depth
would never be evaluated.
This is not the case.
.Pp
The operator
.Cm -or
was implemented as
.Cm -o ,
and the operator
.Cm -and
was implemented as
.Cm -a .
.Pp
Historic implementations of the
.Ic -exec
and
.Ic -ok
primaries did not replace the string
.Qq {}
in the utility name or the
utility arguments if it had preceding or following non-whitespace characters.
This version replaces it no matter where in the utility name or arguments
it appears.
.Sh HISTORY
A
.Nm
command appeared in
.At v1 .
.Sh CAVEATS
The special characters used by
.Nm
are also special characters to many shell programs.
In particular, the characters
.Ql * ,
.Ql [ ,
.Ql \&] ,
.Ql \&? ,
.Ql ( ,
.Ql \&) ,
.Ql \&! ,
.Ql \e ,
and
.Ql \&;
may have to be escaped from the shell.
.Pp
As there is no delimiter separating options and file names or file
names and the
.Ar expression ,
it is difficult to specify files named
.Dq -xdev
or
.Sq \&! .
These problems are handled by the
.Fl f
option and the
.Xr getopt 3
.Sq --
construct.