<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE erlref SYSTEM "erlref.dtd"> <erlref> <header> <copyright> <year>2003</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. </legalnotice> <title>filelib</title> <prepared>Bjorn Gustavsson</prepared> <responsible>Bjorn Gustavsson</responsible> <docno>1</docno> <approved>Kenneth Lundin</approved> <checked></checked> <date>2003-01-21</date> <rev>A</rev> <file>filelib.xml</file> </header> <module>filelib</module> <modulesummary>File utilities, such as wildcard matching of filenames. </modulesummary> <description> <p>This module contains utilities on a higher level than the <seealso marker="kernel:file"><c>file</c></seealso> module.</p> <p>This module does not support "raw" filenames (that is, files whose names do not comply with the expected encoding). Such files are ignored by the functions in this module.</p> <p>For more information about raw filenames, see the <seealso marker="kernel:file"><c>file</c></seealso> module.</p> </description> <datatypes> <datatype> <name name="filename"/> </datatype> <datatype> <name name="dirname"/> </datatype> <datatype> <name name="dirname_all"/> </datatype> <datatype> <name name="filename_all"/> </datatype> </datatypes> <funcs> <func> <name name="ensure_dir" arity="1"/> <fsummary>Ensure that all parent directories for a file or directory exist.</fsummary> <desc> <p>Ensures that all parent directories for the specified file or directory name <c><anno>Name</anno></c> exist, trying to create them if necessary.</p> <p>Returns <c>ok</c> if all parent directories already exist or can be created. Returns <c>{error, <anno>Reason</anno>}</c> if some parent directory does not exist and cannot be created.</p> </desc> </func> <func> <name name="file_size" arity="1"/> <fsummary>Return the size in bytes of a file.</fsummary> <desc> <p>Returns the size of the specified file.</p> </desc> </func> <func> <name name="fold_files" arity="5"/> <fsummary>Fold over all files matching a regular expression.</fsummary> <desc> <p>Folds function <c><anno>Fun</anno></c> over all (regular) files <c><anno>F</anno></c> in directory <c><anno>Dir</anno></c> that match the regular expression <c><anno>RegExp</anno></c> (for a description of the allowed regular expressions, see the <seealso marker="re"><c>re</c></seealso> module). If <c><anno>Recursive</anno></c> is <c>true</c>, all subdirectories to <c>Dir</c> are processed. The regular expression matching is only done on the filename without the directory part.</p> <p>If Unicode filename translation is in effect and the file system is transparent, filenames that cannot be interpreted as Unicode can be encountered, in which case the <c>fun()</c> must be prepared to handle raw filenames (that is, binaries). If the regular expression contains codepoints > 255, it does not match filenames that do not conform to the expected character encoding (that is, are not encoded in valid UTF-8).</p> <p>For more information about raw filenames, see the <seealso marker="kernel:file"><c>file</c></seealso> module.</p> </desc> </func> <func> <name name="is_dir" arity="1"/> <fsummary>Test whether <c>Name</c> refers to a directory.</fsummary> <desc> <p>Returns <c>true</c> if <c><anno>Name</anno></c> refers to a directory, otherwise <c>false</c>.</p> </desc> </func> <func> <name name="is_file" arity="1"/> <fsummary>Test whether <c>Name</c> refers to a file or directory. </fsummary> <desc> <p>Returns <c>true</c> if <c><anno>Name</anno></c> refers to a file or a directory, otherwise <c>false</c>.</p> </desc> </func> <func> <name name="is_regular" arity="1"/> <fsummary>Test whether <c>Name</c> refers to a (regular) file.</fsummary> <desc> <p>Returns <c>true</c> if <c><anno>Name</anno></c> refers to a (regular) file, otherwise <c>false</c>.</p> </desc> </func> <func> <name name="last_modified" arity="1"/> <fsummary>Return the local date and time when a file was last modified. </fsummary> <desc> <p>Returns the date and time the specified file or directory was last modified, or <c>0</c> if the file does not exist.</p> </desc> </func> <func> <name name="wildcard" arity="1"/> <fsummary>Match filenames using Unix-style wildcards.</fsummary> <desc> <p>Returns a list of all files that match Unix-style wildcard string <c><anno>Wildcard</anno></c>.</p> <p>The wildcard string looks like an ordinary filename, except that the following "wildcard characters" are interpreted in a special way:</p> <taglist> <tag>?</tag> <item> <p>Matches one character.</p> </item> <tag>*</tag> <item> <p>Matches any number of characters up to the end of the filename, the next dot, or the next slash.</p> </item> <tag>**</tag> <item> <p>Two adjacent <c>*</c> used as a single pattern match all files and zero or more directories and subdirectories.</p> </item> <tag>[Character1,Character2,...]</tag> <item> <p>Matches any of the characters listed. Two characters separated by a hyphen match a range of characters. Example: <c>[A-Z]</c> matches any uppercase letter.</p> </item> <tag>{Item,...}</tag> <item> <p>Alternation. Matches one of the alternatives.</p> </item> </taglist> <p>Other characters represent themselves. Only filenames that have exactly the same character in the same position match. Matching is case-sensitive, for example, "a" does not match "A".</p> <p>Notice that multiple "*" characters are allowed (as in Unix wildcards, but opposed to Windows/DOS wildcards).</p> <p><em>Examples:</em></p> <p>The following examples assume that the current directory is the top of an Erlang/OTP installation.</p> <p>To find all <c>.beam</c> files in all applications, use the following line:</p> <code type="none"> filelib:wildcard("lib/*/ebin/*.beam").</code> <p>To find <c>.erl</c> or <c>.hrl</c> in all applications <c>src</c> directories, use either of the following lines:</p> <code type="none"> filelib:wildcard("lib/*/src/*.?rl")</code> <code type="none"> filelib:wildcard("lib/*/src/*.{erl,hrl}")</code> <p>To find all <c>.hrl</c> files in <c>src</c> or <c>include</c> directories:</p> <code type="none"> filelib:wildcard("lib/*/{src,include}/*.hrl").</code> <p>To find all <c>.erl</c> or <c>.hrl</c> files in either <c>src</c> or <c>include</c> directories:</p> <code type="none"> filelib:wildcard("lib/*/{src,include}/*.{erl,hrl}")</code> <p>To find all <c>.erl</c> or <c>.hrl</c> files in any subdirectory:</p> <code type="none"> filelib:wildcard("lib/**/*.{erl,hrl}")</code> </desc> </func> <func> <name name="wildcard" arity="2"/> <fsummary>Match filenames using Unix-style wildcards starting at a specified directory.</fsummary> <desc> <p>Same as <seealso marker="#wildcard/1"><c>wildcard/1</c></seealso>, except that <c><anno>Cwd</anno></c> is used instead of the working directory.</p> </desc> </func> </funcs> </erlref>