This manual shows how to find files that meet criteria you specify, and
how to perform various actions on the files that you find. The
principal programs that you use to perform these tasks are find
,
locate
, and xargs
. Some of the examples in this manual
use capabilities specific to the GNU versions of those programs.
GNU find
was originally written by Eric Decker, with enhancements
by David MacKenzie, Jay Plett, and Tim Wood. GNU xargs
was
originally written by Mike Rendell, with enhancements by David
MacKenzie. GNU locate
and its associated utilities were
originally written by James Woods, with enhancements by David MacKenzie.
The idea for `find -print0' and `xargs -0' came from Dan
Bernstein. Many other people have contributed bug fixes, small
improvements, and helpful suggestions. Thanks!
Mail suggestions and bug reports for these programs to
bug-gnu-utils@prep.ai.mit.edu
. Please include the version
number, which you can get by running `find --version'.
For brevity, the word file in this manual means a regular file, a directory, a symbolic link, or any other kind of node that has a directory entry. A directory entry is also called a file name. A file name may contain some, all, or none of the directories in a path that leads to the file. These are all examples of what this manual calls "file names":
parser.c README ./budget/may-94.sc fred/.cshrc /usr/local/include/termcap.h
A directory tree is a directory and the files it contains, all of its subdirectories and the files they contain, etc. It can also be a single non-directory file.
These programs enable you to find the files in one or more directory trees that:
Once you have found the files you're looking for (or files that are potentially the ones you're looking for), you can do more to them than simply list their names. You can get any combination of the files' attributes, or process the files in many ways, either individually or in groups of various sizes. Actions that you might want to perform on the files you have found include, but are not limited to:
This manual describes how to perform each of those tasks, and more.
The principal programs used for making lists of files that match given
criteria and running commands on them are find
, locate
,
and xargs
. An additional command, updatedb
, is used by
system administrators to create databases for locate
to use.
find
searches for files in a directory hierarchy and prints
information about the files it found. It is run like this:
find [file...] [expression]
Here is a typical use of find
. This example prints the names of
all files in the directory tree rooted in `/usr/src' whose name
ends with `.c' and that are larger than 100 Kilobytes.
find /usr/src -name '*.c' -size +100k -print
locate
searches special file name databases for file names that
match patterns. The system administrator runs the updatedb
program to create the databases. locate
is run like this:
locate [option...] pattern...
This example prints the names of all files in the default file name
database whose name ends with `Makefile' or `makefile'. Which
file names are stored in the database depends on how the system
administrator ran updatedb
.
locate '*[Mm]akefile'
The name xargs
, pronounced EX-args, means "combine arguments."
xargs
builds and executes command lines by gathering together
arguments it reads on the standard input. Most often, these arguments
are lists of file names generated by find
. xargs
is run
like this:
xargs [option...] [command [initial-arguments]]
The following command searches the files listed in the file `file-list' and prints all of the lines in them that contain the word `typedef'.
xargs grep typedef < file-list
find
Expressions
The expression that find
uses to select files consists of one or
more primaries, each of which is a separate command line argument
to find
. find
evaluates the expression each time it
processes a file. An expression can contain any of the following types
of primaries:
You can omit the operator between two primaries; it defaults to `-and'. See section Combining Primaries With Operators, for ways to connect primaries into more complex expressions. If the expression contains no actions other than `-prune', `-print' is performed on all files for which the entire expression is true (see section Print File Name).
Options take effect immediately, rather than being evaluated for each file when their place in the expression is reached. Therefore, for clarity, it is best to place them at the beginning of the expression.
Many of the primaries take arguments, which immediately follow them in
the next command line argument to find
. Some arguments are file
names, patterns, or other strings; others are numbers. Numeric
arguments can be specified as
+n
-n
n