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FIND.PRT
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FIND (1)
NAME
find - walk a file hierarchy
SYNOPSIS
find [ dsXx ] [ f ] [ file ] expression
DESCRIPTION
Find recursively descends the directory tree for each file
listed, evaluating an expression (composed of the ``primaries''
and ``operands'' listed below) in terms of each file in the tree.
If file is a symbolic link referencing an existing file, the
directory tree referenced by the link is descended instead of the
link itself.
The options are as follows:
d - The option causes find to perform a depth-first traver-
sal, i.e. directories are visited in post-order and all en-
tries in a directory will be acted on before the directory
itself. By default, find visits directories in pre-order,
i.e. before their contents. Note, the default is not a
breadth-first traversal.
f - The option specifies a file hierarchy for find to
traverse. File hierarchies may also be specified as the
operands immediately following the options.
s - The option causes the file information and file type
(see 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.
X - The option is a modification to permit
to be safely used in conjunction with xargs (1) . If a file
name contains any of the delimiting characters used by xargs
(,) a diagnostic message is displayed on standard error, and
the file is skipped. The delimiting characters include sin-
gle (`` ' '') and double (`` " '') quotes, backslash
(``\''), space, tab and newline characters.
x - The option prevents find from descending into direc-
tories that have a device number different than that of the
file from which the descent began.
PRIMARIES
-atime - True if the difference between the file last access
time and the time find was started, rounded up to the next
full 24-hour period, is n 24-hour periods.
-ctime - True if the difference between the time of last
change of file status information and the time find was
started, rounded up to the next full 24-hour period, is n
24-hour periods.
-exec - True if the program named 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 from
the directory from which find was executed.
-fstype - True if the file is contained in a file system of
type type . Currently supported types are ``local'',
``mfs'', ``nfs'', ``pc'', ``rdonly'' and ``ufs''. The types
``local'' and ``rdonly'' are not specific file system types.
The former matches any file system physically mounted on the
system where the find is being executed and the latter
matches any file system which is mounted read-only.
-group - True if the file belongs to the group gname . If
gname is numeric and there is no such group name, then gname
is treated as a group id.
-inum - True if the file has inode number n .
-links - True if the file has n links.
-ls - This primary always evaluates to true. The following
information for the current file is written to standard out-
put: its inode number, size in 512-byte blocks, file permis-
sions, 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''.
-mtime - True if the difference between the file last modif-
ication time and the time find was started, rounded up to
the next full 24-hour period, is n 24-hour periods.
-ok - The primary is identical to the primary with the ex-
ception that find requests user affirmation for the execu-
tion 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 ok expres-
sion is false.
-name - True if the last component of the pathname being ex-
amined matches pattern . Special shell pattern matching
characters (``['', ``]'', ``*'', and ``?'') may be used as
part of pattern . These characters may be matched explicitly
by escaping them with a backslash (``\'').
-newer - True if the current file has a more recent last
modification time than file .
-nouser - True if the file belongs to an unknown user.
-nogroup - True if the file belongs to an unknown group.
-path - True if the pathname being examined matches pattern
. Special shell pattern matching characters (``['', ``]'',
``*'', and ``?'') may be used as part of pattern . These
characters may be matched explicitly by escaping them with a
backslash (``\''). Slashes (``/'') are treated as normal
characters and do not have to be matched explicitly.
-perm - The mode may be either symbolic (see 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 ex-
actly match the file's mode bits. Note, the first character
of a symbolic mode may not be a dash (``-'').
-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 or is specified.
-prune - This primary always evaluates to true. It causes
find to not descend into the current file. Note, the pri-
mary has no effect if the option was specified.
-size - True if the file's size, rounded up, in 512-byte
blocks is n . If n is followed by a ``c'', then the primary
is true if the file's size is n bytes.
-type - True if the file is of the specified type. Possible
file types are as follows:
b - block special
c - character special
d - directory
f - regular file
l - symbolic link
p - FIFO
s - socket
-user - True if the file belongs to the user uname . If
uname is numeric and there is no such user name, then uname
is treated as a user id.
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 n'', a preceding minus sign
means ``less than n'' and neither means ``exactly n'' .
OPERATORS
The primaries may be combined using the following operators.
The operators are listed in order of decreasing precedence.
( - This evaluates to true if the parenthesized expression
evaluates to true.
! - This is the unary operator. It evaluates to true if
the expression is false.
expression -
expression - The operator is the logical 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.
expression - The operator is the logical 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.
All operands and primaries must be separate arguments to find
Primaries which themselves take arguments expect each argument to
be a separate argument to find
EXAMPLES
The following examples are shown as given to the shell:
find / \! -name *.c -print - Print out a list of all
the files whose names do not end in ``.c''.
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''.
find / \! \( -newer ttt -user wnj \) -print - Print
out a list of all the files which are not both newer than
``ttt'' and owned by ``wnj''.
find / \( -newer ttt -or -user wnj \) -print - Print
out a list of all the files that are either owned by ``wnj''
or that are newer than ``ttt''.
SEE ALSO
chmod (1) , sh (1) , test (1) , stat (2) , umask (2) , getpwent
(3) , getgrent (3) , strmode (3)
STANDARDS
The find utility syntax is a superset of the syntax specified
by the standard.
The and options and the and primaries are extensions to
Historically, the and options were implemented using the pri-
maries ``-depth'', ``-follow'', and ``-xdev''. These primaries
always evaluated to true. As they were really global variables
that took effect before the traversal began, some legal expres-
sions could have unexpected results. An example is the expres-
sion ``-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.
The operator ``-or'' was implemented as ``-o'', and the opera-
tor ``-and'' was implemented as ``-a''.
Historic implementations of the and primaries did not replace
the string ``{}'' 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 argu-
ments it appears.
BUGS
The special characters used by find are also special characters
to many shell programs. In particular, the characters ``*'',
``['', ``]'', ``?'', ``('', ``)'', ``!'', ``\'' and ``;'' may
have to be escaped from the shell.
As there is no delimiter separating options and file names or
file names and the expression , it is difficult to specify files
named ``-xdev'' or ``!''. These problems are handled by the op-
tion and the getopt (3) ``--'' construct.