(PHP 4, PHP 5)
fopen — Opens file or URL
fopen() binds a named resource, specified by filename , to a stream.
If filename is of the form "scheme://...", it is assumed to be a URL and PHP will search for a protocol handler (also known as a wrapper) for that scheme. If no wrappers for that protocol are registered, PHP will emit a notice to help you track potential problems in your script and then continue as though filename specifies a regular file.
If PHP has decided that filename specifies a local file, then it will try to open a stream on that file. The file must be accessible to PHP, so you need to ensure that the file access permissions allow this access. If you have enabled 안전 모드, or open_basedir further restrictions may apply.
If PHP has decided that filename specifies a registered protocol, and that protocol is registered as a network URL, PHP will check to make sure that allow_url_fopen is enabled. If it is switched off, PHP will emit a warning and the fopen call will fail.
Note: The list of supported protocols can be found in 지원 프로토콜/래퍼 목록. Some protocols (also referred to as wrappers) support context and/or php.ini options. Refer to the specific page for the protocol in use for a list of options which can be set. (e.g. php.ini value user_agent used by the http wrapper).
On the Windows platform, be careful to escape any backslashes used in the path to the file, or use forward slashes.
<?php
$handle = fopen("c:\\data\\info.txt", "r");
?>
The mode parameter specifies the type of access you require to the stream. It may be any of the following:
mode | Description |
---|---|
'r' | Open for reading only; place the file pointer at the beginning of the file. |
'r+' | Open for reading and writing; place the file pointer at the beginning of the file. |
'w' | Open for writing only; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it. |
'w+' | Open for reading and writing; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it. |
'a' | Open for writing only; place the file pointer at the end of the file. If the file does not exist, attempt to create it. |
'a+' | Open for reading and writing; place the file pointer at the end of the file. If the file does not exist, attempt to create it. |
'x' | Create and open for writing only; place the file pointer at the beginning of the file. If the file already exists, the fopen() call will fail by returning FALSE and generating an error of level E_WARNING. If the file does not exist, attempt to create it. This is equivalent to specifying O_EXCL|O_CREAT flags for the underlying open(2) system call. |
'x+' | Create and open for reading and writing; place the file pointer at the beginning of the file. If the file already exists, the fopen() call will fail by returning FALSE and generating an error of level E_WARNING. If the file does not exist, attempt to create it. This is equivalent to specifying O_EXCL|O_CREAT flags for the underlying open(2) system call. |
Note: Different operating system families have different line-ending conventions. When you write a text file and want to insert a line break, you need to use the correct line-ending character(s) for your operating system. Unix based systems use \n as the line ending character, Windows based systems use \r\n as the line ending characters and Macintosh based systems use \r as the line ending character.
If you use the wrong line ending characters when writing your files, you might find that other applications that open those files will "look funny".
Windows offers a text-mode translation flag ('t') which will transparently translate \n to \r\n when working with the file. In contrast, you can also use 'b' to force binary mode, which will not translate your data. To use these flags, specify either 'b' or 't' as the last character of the mode parameter.
The default translation mode depends on the SAPI and version of PHP that you are using, so you are encouraged to always specify the appropriate flag for portability reasons. You should use the 't' mode if you are working with plain-text files and you use \n to delimit your line endings in your script, but expect your files to be readable with applications such as notepad. You should use the 'b' in all other cases.
If you do not specify the 'b' flag when working with binary files, you may experience strange problems with your data, including broken image files and strange problems with \r\n characters.
Note: For portability, it is strongly recommended that you always use the 'b' flag when opening files with fopen().
Note: Again, for portability, it is also strongly recommended that you re-write code that uses or relies upon the 't' mode so that it uses the correct line endings and 'b' mode instead.
The optional third use_include_path parameter can be set to '1' or TRUE if you want to search for the file in the include_path, too.
Note: Context 지원은 PHP 5.0.0에서 추가되었습니다. contexts에 관한 자세한 설명은 Stream 함수 목록을 참고하십시오.
Returns a file pointer resource on success, or FALSE on error.
If the open fails, the function an error of level E_WARNING is generated. You may use @ to suppress this warning.
버전 | 설명 |
---|---|
4.3.2 | As of PHP 4.3.2, the default mode is set to binary for all platforms that distinguish between binary and text mode. If you are having problems with your scripts after upgrading, try using the 't' flag as a workaround until you have made your script more portable as mentioned below |
4.3.2 | The 'x' and 'x+' option was added |
Example #1 fopen() examples
<?php
$handle = fopen("/home/rasmus/file.txt", "r");
$handle = fopen("/home/rasmus/file.gif", "wb");
$handle = fopen("http://www.example.com/", "r");
$handle = fopen("ftp://user:password@example.com/somefile.txt", "w");
?>
SSL을 사용할 때, 마이크로소프트 IIS는 close_notify 식별자를 보내지 않은채 접속을 종료하는 프로토콜 오류가 있습니다. PHP는 데이터의 마지막에 도달했을때, 이를 "SSL: Fatal Protocol Error"로 보고합니다. 이를 처리하기 위해서는 error_reporting 레벨에 경고를 포함하지 않도록 해야합니다. PHP 4.3.7 이후는 https:// 래퍼를 통해 스트림을 열 때, 문제가 있는 IIS 서버 소프트웨어를 검출하여 경고를 하지 않습니다. ssl:// 소켓을 만들기 위해 fsockopen()을 사용한다면, 경고를 직접 검출하여 없애야 합니다.
Note: 안전 모드를 활성화했을 경우, PHP는 작업하려는 디렉토리가 실행중인 스크립트와 같은 UID(owner)를 가지고 있는지 확인합니다.
If you are experiencing problems with reading and writing to files and you're using the server module version of PHP, remember to make sure that the files and directories you're using are accessible to the server process.