Filesystem basename Returns filename component of path string basename string path string suffix Given a string containing a path to a file, this function will return the base name of the file. If the filename ends in suffix this will also be cut off. On Windows, both slash (/) and backslash (\) are used as path separator character. In other environments, it is the forward slash (/). The suffix parameter was added in PHP 4.1.0. See also: dirname chgrp Changes file group int chgrp string filename mixed group Attempts to change the group of the file filename to group. Only the superuser may change the group of a file arbitrarily; other users may change the group of a file to any group of which that user is a member. Returns &true; on success; otherwise returns &false;. See also chown and chmod. This function does not work on Windows systems chmod Changes file mode int chmod string filename int mode Attempts to change the mode of the file specified by filename to that given in mode. Note that mode is not automatically assumed to be an octal value, so strings (such as "g+w") will not work properly. To ensure the expected operation, you need to prefix mode with a zero (0): Returns &true; on success and &false; otherwise. See also chown and chgrp. This function does not work on Windows systems chown Changes file owner int chown string filename mixed user Attempts to change the owner of the file filename to user user. Only the superuser may change the owner of a file. Returns &true; on success; otherwise returns &false;. See also chown and chmod. This function does not work on Windows systems clearstatcache Clears file stat cache void clearstatcache Invoking the stat or lstat system call on most systems is quite expensive. Therefore, the result of the last call to any of the status functions (listed below) is stored for use on the next such call using the same filename. If you wish to force a new status check, for instance if the file is being checked many times and may change or disappear, use this function to clear the results of the last call from memory. This value is only cached for the lifetime of a single request. Affected functions include stat, lstat, file_exists, is_writable, is_readable, is_executable, is_file, is_dir, is_link, filectime, fileatime, filemtime, fileinode, filegroup, fileowner, filesize, filetype, and fileperms. copy Copies file int copy string source string dest Makes a copy of a file. Returns &true; if the copy succeeded, &false; otherwise. \n"); } ]]> See also: rename. delete A dummy manual entry void delete string file This is a dummy manual entry to satisfy those people who are looking for unlink or unset in the wrong place. See also: unlink to delete files, unset to delete variables. dirname Returns directory name component of path string dirname string path Given a string containing a path to a file, this function will return the name of the directory. On Windows, both slash (/) and backslash (\) are used as path separator character. In other environments, it is the forward slash (/). See also: basename disk_free_space Returns available space in directory float disk_free_space string directory Given a string containing a directory, this function will return the number of bytes available on the corresponding filesystem or disk partition. diskfreespace Alias of disk_free_space float diskfreespace string directory This is a deprecated alias of disk_free_space. Use that function instead. disk_total_space Returns the total size of a directory float disk_total_space string directory Given a string containing a directory, this function will return the total number of bytes on the corresponding filesystem or disk partition. fclose Closes an open file pointer bool fclose int fp The file pointed to by fp is closed. Returns &true; on success and &false; on failure. The file pointer must be valid, and must point to a file successfully opened by fopen or fsockopen. feof Tests for end-of-file on a file pointer int feof int fp Returns &true; if the file pointer is at EOF or an error occurs; otherwise returns &false;. The file pointer must be valid, and must point to a file successfully opened by fopen, popen, or fsockopen. fflush Flushes the output to a file int fflush int fp This function forces a write of all buffered output to the to the resource pointed to by the file handle fp. Returns &true; if succesful, &false; otherwise. The file pointer must be valid, and must point to a file successfully opened by fopen, popen, or fsockopen. fgetc Gets character from file pointer string fgetc int fp Returns a string containing a single character read from the file pointed to by fp. Returns &false; on EOF. The file pointer must be valid, and must point to a file successfully opened by fopen, popen, or fsockopen. See also fread, fopen, popen, fsockopen, and fgets. fgetcsv Gets line from file pointer and parse for CSV fields array fgetcsv int fp int length string delimiter Similar to fgets except that fgetcsv parses the line it reads for fields in CSV format and returns an array containing the fields read. The field delimiter is a comma, unless you specify another delimiter with the optional third parameter. Fp must be a valid file pointer to a file successfully opened by fopen, popen, or fsockopen Length must be greater than the longest line to be found in the CSV file (allowing for trailing line-end characters). fgetcsv returns &false; on error, including end of file. N.B. A blank line in a CSV file will be returned as an array comprising a single &null; field, and will not be treated as an error. $num fields in line $row:
"; $row++; for ($c=0; $c < $num; $c++) { print $data[$c] . "
"; } } fclose ($fp); ]]> fgets Gets line from file pointer string fgets int fp int length Returns a string of up to length - 1 bytes read from the file pointed to by fp. Reading ends when length - 1 bytes have been read, on a newline (which is included in the return value), or on EOF (whichever comes first). If an error occurs, returns &false;. Common Pitfalls: People used to the 'C' semantics of fgets should note the difference in how EOF is returned. The file pointer must be valid, and must point to a file successfully opened by fopen, popen, or fsockopen. A simple example follows: See also fread, fopen, popen, fgetc, fsockopen, and socket_set_timeout. fgetss Gets line from file pointer and strip HTML tags string fgetss int fp int length string allowable_tags Identical to fgets, except that fgetss attempts to strip any HTML and PHP tags from the text it reads. You can use the optional third parameter to specify tags which should not be stripped. allowable_tags was added in PHP 3.0.13, PHP4B3. See also fgets, fopen, fsockopen, popen, and strip_tags. file Reads entire file into an array array file string filename int use_include_path Identical to readfile, except that file returns the file in an array. Each element of the array corresponds to a line in the file, with the newline still attached. You can use the optional second parameter and set it to "1", if you want to search for the file in the include_path, too. Line $line_num:; " . htmlspecialchars ($line) . "
\n"; } // get a web page into a string $fcontents = join ('', file ('http://www.php.net')); ?> ]]> See also readfile, fopen, fsockopen, and popen. file_exists Checks whether a file exists bool file_exists string filename Returns &true; if the file specified by filename exists; &false; otherwise. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. The results of this function are cached. See clearstatcache for more details. fileatime Gets last access time of file int fileatime string filename Returns the time the file was last accessed, or &false; in case of an error. The time is returned as a Unix timestamp. The results of this function are cached. See clearstatcache for more details. Note: The atime of a file is supposed to change whenever the data blocks of a file are being read. This can be costly performancewise when an application regularly accesses a very large number of files or directories. Some Unix filesystems can be mounted with atime updates disabled to increase the performance of such applications; USENET news spools are a common example. On such filesystems this function will be useless. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. filectime Gets inode change time of file int filectime string filename Returns the time the file was last changed, or &false; in case of an error. The time is returned as a Unix timestamp. The results of this function are cached. See clearstatcache for more details. Note: In most Unix filesystems, a file is considered changed when its inode data is changed; that is, when the permissions, owner, group, or other metadata from the inode is updated. See also filemtime (which is what you want to use when you want to create "Last Modified" footers on web pages) and fileatime. Note also that in some Unix texts the ctime of a file is referred to as being the creation time of the file. This is wrong. There is no creation time for Unix files in most Unix filesystems. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. filegroup Gets file group int filegroup string filename Returns the group ID of the owner of the file, or &false; in case of an error. The group ID is returned in numerical format, use posix_getgrgid to resolve it to a group name. The results of this function are cached. See clearstatcache for more details. This function does not work on Windows systems This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. fileinode Gets file inode int fileinode string filename Returns the inode number of the file, or &false; in case of an error. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. This function does not work on Windows systems filemtime Gets file modification time int filemtime string filename Returns the time the file was last modified, or &false; in case of an error. The time is returned as a Unix timestamp. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. Note: This function returns the time when the data blocks of a file were being written to, that is, the time when the content of the file was changed. Use date on the result of this function to get a printable modification date for use in page footers. fileowner Gets file owner int fileowner string filename Returns the user ID of the owner of the file, or &false; in case of an error. The user ID is returned in numerical format, use posix_getpwuid to resolve it to a username. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. This function does not work on Windows systems fileperms Gets file permissions int fileperms string filename Returns the permissions on the file, or &false; in case of an error. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. The results of this function are cached. See clearstatcache for more details. filesize Gets file size int filesize string filename Returns the size of the file, or &false; in case of an error. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. filetype Gets file type string filetype string filename Returns the type of the file. Possible values are fifo, char, dir, block, link, file, and unknown. Returns &false; if an error occurs. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. flock Portable advisory file locking bool flock int fp int operation int wouldblock PHP supports a portable way of locking complete files in an advisory way (which means all accessing programs have to use the same way of locking or it will not work). flock operates on fp which must be an open file pointer. operation is one of the following values: To acquire a shared lock (reader), set operation to LOCK_SH (set to 1 prior to PHP 4.0.1). To acquire an exclusive lock (writer), set operation to LOCK_EX (set to 2 prior to PHP 4.0.1). To release a lock (shared or exclusive), set operation to LOCK_UN (set to 3 prior to PHP 4.0.1). If you don't want flock to block while locking, add LOCK_NB (4 prior to PHP 4.0.1) to operation. flock allows you to perform a simple reader/writer model which can be used on virtually every platform (including most Unices and even Windows). The optional 3rd argument is set to &true; if the lock would block (EWOULDBLOCK errno condition) flock returns &true; on success and &false; on error (e.g. when a lock could not be acquired). On most operation systems flock is implemented at the process level. When using a multithreaded server API like ISAPI you cannot rely on flock to protect files against other PHP scripts running in parallel threads of the same server instance! fopen Opens file or URL int fopen string filename string mode int use_include_path If filename begins with "http://" (not case sensitive), an HTTP 1.0 connection is opened to the specified server, the page is requested using the HTTP GET method, and a file pointer is returned to the beginning of the body of the response. A 'Host:' header is sent with the request in order to handle name-based virtual hosts. Note that the file pointer allows you to retrieve only the body of the response; you cannot access the HTTP response header using this function. Versions prior to PHP 4.0.5 do not handle HTTP redirects. Because of this, directories must include trailing slashes. If filename begins with "ftp://" (not case sensitive), an ftp connection to the specified server is opened and a pointer to the requested file is returned. If the server does not support passive mode ftp, this will fail. You can open files for either reading or writing via ftp (but not both simultaneously). If filename is one of "php://stdin", "php://stdout", or "php://stderr", the corresponding stdio stream will be opened. (This was introduced in PHP 3.0.13; in earlier versions, a filename such as "/dev/stdin" or "/dev/fd/0" must be used to access the stdio streams.) If filename begins with anything else, the file will be opened from the filesystem, and a file pointer to the file opened is returned. If the open fails, the function returns &false;. mode may be any of the following: '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. The mode may contain the letter 'b'. This is useful only on systems which differentiate between binary and text files (i.e. Windows. It's useless on Unix). If not needed, this will be ignored. You can use the optional third parameter and set it to "1", if you want to search for the file in the include_path, too. 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. On the Windows platform, be careful to escape any backslashes used in the path to the file, or use forward slashes. See also fclose, fsockopen, socket_set_timeout, and popen. fpassthru Output all remaining data on a file pointer int fpassthru int fp Reads to EOF on the given file pointer and writes the results to standard output. If an error occurs, fpassthru returns &false;. The file pointer must be valid, and must point to a file successfully opened by fopen, popen, or fsockopen. The file is closed when fpassthru is done reading it (leaving fp useless). If you just want to dump the contents of a file to stdout you may want to use the readfile, which saves you the fopen call. See also readfile, fopen, popen, and fsockopen fputs Writes to a file pointer int fputs int fp string str int length fputs is an alias to fwrite, and is identical in every way. Note that the length parameter is optional and if not specified the entire string will be written. fread Binary-safe file read string fread int fp int length fread reads up to length bytes from the file pointer referenced by fp. Reading stops when length bytes have been read or EOF is reached, whichever comes first. On systems which differentiate between binary and text files (i.e. Windows) the file must be opened with 'b' included in fopen mode parameter. See also fwrite, fopen, fsockopen, popen, fgets, fgetss, fscanf, file, and fpassthru. fscanf Parses input from a file according to a format mixed fscanf int handle string format string var1... The function fscanf is similar to sscanf, but it takes its input from a file associated with handle and interprets the input according to the specified format. If only two parameters were passed to this function, the values parsed will be returned as an array. Otherwise, if optional parameters are passed, the function will return the number of assigned values. The optional parameters must be passed by reference. See also fread, fgets, fgetss, sscanf, printf, and sprintf. fseek Seeks on a file pointer int fseek int fp int offset int whence Sets the file position indicator for the file referenced by fp.The new position, measured in bytes from the beginning of the file, is obtained by adding offset to the position specified by whence, whose values are defined as follows: SEEK_SET - Set position equal to offset bytes. SEEK_CUR - Set position to current location plus offset. SEEK_END - Set position to end-of-file plus offset. If whence is not specified, it is assumed to be SEEK_SET. Upon success, returns 0; otherwise, returns -1. Note that seeking past EOF is not considered an error. May not be used on file pointers returned by fopen if they use the "http://" or "ftp://" formats. The whence argument was added after PHP 4.0 RC1. See also ftell and rewind. fstat Gets information about a file using an open file pointer array fstat int fp Gathers the statistics of the file opened by the file pointer fp. This function is similar to the stat function except that it operates on an open file pointer instead of a filename. Returns an array with the statistics of the file with the following elements: device inode number of links user id of owner group id owner device type if inode device * size in bytes time of last access time of last modification time of last change blocksize for filesystem I/O * number of blocks allocated * - only valid on systems supporting the st_blksize type--other systems (i.e. Windows) return -1 The results of this function are cached. See clearstatcache for more details. ftell Tells file pointer read/write position int ftell int fp Returns the position of the file pointer referenced by fp; i.e., its offset into the file stream. If an error occurs, returns &false;. The file pointer must be valid, and must point to a file successfully opened by fopen or popen. See also fopen, popen, fseek and rewind. ftruncate Truncates a file to a given length. int ftruncate int fp int size Takes the filepointer, fp, and truncates the file to length, size. This function returns &true; on success and &false; on failure. fwrite Binary-safe file write int fwrite int fp string string int length fwrite writes the contents of string to the file stream pointed to by fp. If the length argument is given, writing will stop after length bytes have been written or the end of string is reached, whichever comes first. Note that if the length argument is given, then the magic_quotes_runtime configuration option will be ignored and no slashes will be stripped from string. On systems which differentiate between binary and text files (i.e. Windows) the file must be opened with 'b' included in fopen mode parameter. See also fread, fopen, fsockopen, popen, and fputs. set_file_buffer Sets file buffering on the given file pointer int set_file_buffer int fp int buffer Output using fwrite is normally buffered at 8K. This means that if there are two processess wanting to write to the same output stream (a file), each is paused after 8K of data to allow the other to write. set_file_buffer sets the buffering for write operations on the given filepointer fp to buffer bytes. If buffer is 0 then write operations are unbuffered. This ensures that all writes with fwrite are completed before other processes are allowed to write to that output stream. The function returns 0 on success, or EOF if the request cannot be honored. The following example demonstrates how to use set_file_buffer to create an unbuffered stream. See also fopen, fwrite. is_dir Tells whether the filename is a directory bool is_dir string filename Returns &true; if the filename exists and is a directory. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. See also is_file and is_link. is_executable Tells whether the filename is executable bool is_executable string filename Returns &true; if the filename exists and is executable. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. See also is_file and is_link. is_file Tells whether the filename is a regular file bool is_file string filename Returns &true; if the filename exists and is a regular file. The results of this function are cached. See clearstatcache for more details. See also is_dir and is_link. is_link Tells whether the filename is a symbolic link bool is_link string filename Returns &true; if the filename exists and is a symbolic link. The results of this function are cached. See clearstatcache for more details. See also is_dir and is_file. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. This function does not work on Windows systems is_readable Tells whether the filename is readable bool is_readable string filename Returns &true; if the filename exists and is readable. Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody'). Safe mode limitations are not taken into account. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. See also is_writable. is_writable Tells whether the filename is writable bool is_writable string filename Returns &true; if the filename exists and is writable. The filename argument may be a directory name allowing you to check if a directory is writeable. Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody'). Safe mode limitations are not taken into account. The results of this function are cached. See clearstatcache for more details. This function will not work on remote files; the file to be examined must be accessible via the server's filesystem. See also is_readable. is_writeable Tells whether the filename is writable bool is_writeable string filename This is an alias for is_writable is_uploaded_file Tells whether the file was uploaded via HTTP POST. bool is_uploaded_file string filename This function is available only in versions of PHP 3 after PHP 3.0.16, and in versions of PHP 4 after 4.0.2. Returns &true; if the file named by filename was uploaded via HTTP POST. This is useful to help ensure that a malicious user hasn't tried to trick the script into working on files upon which it should not be working--for instance, /etc/passwd. This sort of check is especially important if there is any chance that anything done with uploaded files could reveal their contents to the user, or even to other users on the same system. See also move_uploaded_file, and the section Handling file uploads for a simple usage example. link Create a hard link int link string target string link link creates a hard link. See also the symlink to create soft links, and readlink along with linkinfo. This function does not work on Windows systems linkinfo Gets information about a link int linkinfo string path linkinfo returns the st_dev field of the UNIX C stat structure returned by the lstat system call. This function is used to verify if a link (pointed to by path) really exists (using the same method as the S_ISLNK macro defined in stat.h). Returns 0 or &false; in case of error. See also symlink, link, and readlink. This function does not work on Windows systems mkdir Makes directory int mkdir string pathname int mode Attempts to create the directory specified by pathname. Note that you probably want to specify the mode as an octal number, which means it should have a leading zero. The mode is also modified by the current umask, which you can change using umask. Returns &true; on success and &false; on failure. See also rmdir. move_uploaded_file Moves an uploaded file to a new location. bool move_uploaded_file string filename string destination This function is available only in versions of PHP 3 after PHP 3.0.16, and in versions of PHP 4 after 4.0.2. This function checks to ensure that the file designated by filename is a valid upload file (meaning that it was uploaded via PHP's HTTP POST upload mechanism). If the file is valid, it will be moved to the filename given by destination. If filename is not a valid upload file, then no action will occur, and move_uploaded_file will return &false;. If filename is a valid upload file, but cannot be moved for some reason, no action will occur, and move_uploaded_file will return &false;. Additionally, a warning will be issued. This sort of check is especially important if there is any chance that anything done with uploaded files could reveal their contents to the user, or even to other users on the same system. ¬e.sm.uidcheck; See also is_uploaded_file, and the section Handling file uploads for a simple usage example. parse_ini_file Parse a configuration file array parse_ini_file string filename bool process_sections parse_ini_file loads in the ini file specified in filename, and returns the settings in it in an associative array. By setting the last process_sections parameter to &true;, you get a multidimensional array, with the section names and settings included. The default for process_sections is &false; This function has nothing to do with the php.ini file. It is already processed, the time you run your script. This function can be used to read in your own application's configuration files. The structure of the ini file is similar to that of the php.ini's. ]]> Would produce: 1 [five] => 5 [path] => /usr/local/bin ) Array ( [first_section] => Array ( [one] => 1 [five] => 5 ) [second_section] => Array ( [path] => /usr/local/bin ) ) ]]> pathinfo Returns information about a file path array pathinfo string path pathinfo returns an associative array containing information about path. The following array elements are returned: dirname, basename and extension. ]]> Would produce: See also dirname, basename, parse_url and realpath. pclose Closes process file pointer int pclose int fp Closes a file pointer to a pipe opened by popen. The file pointer must be valid, and must have been returned by a successful call to popen. Returns the termination status of the process that was run. See also popen. popen Opens process file pointer int popen string command string mode Opens a pipe to a process executed by forking the command given by command. Returns a file pointer identical to that returned by fopen, except that it is unidirectional (may only be used for reading or writing) and must be closed with pclose. This pointer may be used with fgets, fgetss, and fputs. If an error occurs, returns &false;. See also pclose. readfile Outputs a file int readfile string filename int use_include_path Reads a file and writes it to standard output. Returns the number of bytes read from the file. If an error occurs, &false; is returned and unless the function was called as @readfile, an error message is printed. If filename begins with "http://" (not case sensitive), an HTTP 1.0 connection is opened to the specified server and the text of the response is written to standard output. Versions prior to PHP 4.0.5 do not handle HTTP redirects. Because of this, directories must include trailing slashes. If filename begins with "ftp://" (not case sensitive), an ftp connection to the specified server is opened and the requested file is written to standard output. If the server does not support passive mode ftp, this will fail. If filename begins with neither of these strings, the file will be opened from the filesystem and its contents written to standard output. You can use the optional second parameter and set it to "1", if you want to search for the file in the include_path, too. See also fpassthru, file, fopen, include, require, and virtual. readlink Returns the target of a symbolic link string readlink string path readlink does the same as the readlink C function and returns the contents of the symbolic link path or 0 in case of error. See also symlink, readlink and linkinfo. This function does not work on Windows systems rename Renames a file int rename string oldname string newname Attempts to rename oldname to newname. Returns &true; on success and &false; on failure. rewind Rewind the position of a file pointer int rewind int fp Sets the file position indicator for fp to the beginning of the file stream. If an error occurs, returns 0. The file pointer must be valid, and must point to a file successfully opened by fopen. See also fseek and ftell. rmdir Removes directory int rmdir string dirname Attempts to remove the directory named by pathname. The directory must be empty, and the relevant permissions must permit. this. If an error occurs, returns 0. See also mkdir. stat Gives information about a file array stat string filename Gathers the statistics of the file named by filename. Returns an array with the statistics of the file with the following elements: device inode inode protection mode number of links user id of owner group id owner device type if inode device * size in bytes time of last access time of last modification time of last change blocksize for filesystem I/O * number of blocks allocated * - only valid on systems supporting the st_blksize type--other systems (i.e. Windows) return -1. Returns &false; in case of error. stat doesn't handle URL as does fopen. The results of this function are cached. See clearstatcache for more details. lstat Gives information about a file or symbolic link array lstat string filename Gathers the statistics of the file or symbolic link named by filename. This function is identical to the stat function except that if the filename parameter is a symbolic link, the status of the symbolic link is returned, not the status of the file pointed to by the symbolic link. Returns an array with the statistics of the file with the following elements: device inode inode protection mode number of links user id of owner group id owner device type if inode device * size in bytes time of last access time of last modification time of last change blocksize for filesystem I/O * number of blocks allocated * - only valid on systems supporting the st_blksize type--other systems (i.e. Windows) return -1 The results of this function are cached. See clearstatcache for more details. realpath Returns canonicalized absolute pathname string realpath string path realpath expands all symbolic links and resolves references to '/./', '/../' and extra '/' characters in the input path and return the canonicalized absolute pathname. The resulting path will have no symbolic link, '/./' or '/../' components. symlink Creates a symbolic link int symlink string target string link symlink creates a symbolic link from the existing target with the specified name link. See also link to create hard links, and readlink along with linkinfo. This function does not work on Windows systems. tempnam Create file with unique file name string tempnam string dir string prefix Creates a file with a unique filename in the specified directory. If the directory does not exist, tempnam may generate a filename in the system's temporary directory. Prior to PHP 4.0.6, the behaviour of the tempnam function was system dependent. On Windows the TMP environment variable will override the dir parameter, on Linux the TMPDIR environment variable has precedence, while SVR4 will always use your dir parameter if the directory it points to exists. Consult your system documentation on the tempnam(3) function if in doubt. Returns the new temporary filename, or the &false; string on failure. This function's behavior changed in 4.0.3. The temporary file is also created to avoid a race condition where the file might appear in the filesystem between the time the string was generated and before the the script gets around to creating the file. See also tmpfile. tmpfile Creates a temporary file int tmpfile Creates a temporary file with an unique name in write mode, returning a file handle similar to the one returned by fopen. The file is automatically removed when closed (using fclose), or when the script ends. For details, consult your system documentation on the tmpfile(3) function, as well as the stdio.h header file. See also tempnam. touch Sets modification time of file int touch string filename int time Attempts to set the modification time of the file named by filename to the value given by time. If the option time is not given, uses the present time. If the file does not exist, it is created. Returns &true; on success and &false; otherwise. umask Changes the current umask int umask int mask umask sets PHP's umask to mask & 0777 and returns the old umask. When PHP is being used as a server module, the umask is restored when each request is finished. umask without arguments simply returns the current umask. This function may not work on Windows systems. unlink Deletes a file int unlink string filename Deletes filename. Similar to the Unix C unlink() function. Returns 0 or &false; on an error. See also rmdir for removing directories. This function may not work on Windows systems.