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diff --git a/doc/html/qfile.html b/doc/html/qfile.html new file mode 100644 index 0000000..17af0da --- /dev/null +++ b/doc/html/qfile.html @@ -0,0 +1,503 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<!-- /home/espenr/tmp/qt-3.3.8-espenr-2499/qt-x11-free-3.3.8/src/tools/qfile.cpp:77 --> +<html> +<head> +<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"> +<title>QFile Class</title> +<style type="text/css"><!-- +fn { margin-left: 1cm; text-indent: -1cm; } +a:link { color: #004faf; text-decoration: none } +a:visited { color: #672967; text-decoration: none } +body { background: #ffffff; color: black; } +--></style> +</head> +<body> + +<table border="0" cellpadding="0" cellspacing="0" width="100%"> +<tr bgcolor="#E5E5E5"> +<td valign=center> + <a href="index.html"> +<font color="#004faf">Home</font></a> + | <a href="classes.html"> +<font color="#004faf">All Classes</font></a> + | <a href="mainclasses.html"> +<font color="#004faf">Main Classes</font></a> + | <a href="annotated.html"> +<font color="#004faf">Annotated</font></a> + | <a href="groups.html"> +<font color="#004faf">Grouped Classes</font></a> + | <a href="functions.html"> +<font color="#004faf">Functions</font></a> +</td> +<td align="right" valign="center"><img src="logo32.png" align="right" width="64" height="32" border="0"></td></tr></table><h1 align=center>QFile Class Reference</h1> + +<p>The QFile class is an I/O device that operates on files. +<a href="#details">More...</a> +<p>Almost all the functions in this class are <a href="threads.html#reentrant">reentrant</a> when Qt is built with thread support. The exceptions are <a href="#setEncodingFunction"><b>setEncodingFunction</b></a>(), <a href="#setDecodingFunction"><b>setDecodingFunction</b></a>(), and <a href="#setErrorString"><b>setErrorString</b></a>(). +</p><p><tt>#include <<a href="qfile-h.html">qfile.h</a>></tt> +<p>Inherits <a href="qiodevice.html">QIODevice</a>. +<p><a href="qfile-members.html">List of all member functions.</a> +<h2>Public Members</h2> +<ul> +<li class=fn><a href="#QFile"><b>QFile</b></a> ()</li> +<li class=fn><a href="#QFile-2"><b>QFile</b></a> ( const QString & name )</li> +<li class=fn><a href="#~QFile"><b>~QFile</b></a> ()</li> +<li class=fn>QString <a href="#name"><b>name</b></a> () const</li> +<li class=fn>void <a href="#setName"><b>setName</b></a> ( const QString & name )</li> +<li class=fn>typedef QCString (* <a href="#EncoderFn"><b>EncoderFn</b></a> ) ( const QString & fileName )</li> +<li class=fn>typedef QString (* <a href="#DecoderFn"><b>DecoderFn</b></a> ) ( const QCString & localfileName )</li> +<li class=fn>bool <a href="#exists-2"><b>exists</b></a> () const</li> +<li class=fn>bool <a href="#remove"><b>remove</b></a> ()</li> +<li class=fn>virtual bool <a href="#open"><b>open</b></a> ( int m )</li> +<li class=fn>bool <a href="#open-2"><b>open</b></a> ( int m, FILE * f )</li> +<li class=fn>bool <a href="#open-3"><b>open</b></a> ( int m, int f )</li> +<li class=fn>virtual void <a href="#close"><b>close</b></a> ()</li> +<li class=fn>virtual void <a href="#flush"><b>flush</b></a> ()</li> +<li class=fn>virtual Offset <a href="#size"><b>size</b></a> () const</li> +<li class=fn>virtual bool <a href="#atEnd"><b>atEnd</b></a> () const</li> +<li class=fn>virtual Q_LONG <a href="#readLine"><b>readLine</b></a> ( char * p, Q_ULONG maxlen )</li> +<li class=fn>Q_LONG <a href="#readLine-2"><b>readLine</b></a> ( QString & s, Q_ULONG maxlen )</li> +<li class=fn>virtual int <a href="#getch"><b>getch</b></a> ()</li> +<li class=fn>virtual int <a href="#putch"><b>putch</b></a> ( int ch )</li> +<li class=fn>virtual int <a href="#ungetch"><b>ungetch</b></a> ( int ch )</li> +<li class=fn>int <a href="#handle"><b>handle</b></a> () const</li> +<li class=fn>QString <a href="#errorString"><b>errorString</b></a> () const</li> +</ul> +<h2>Static Public Members</h2> +<ul> +<li class=fn>QCString <a href="#encodeName"><b>encodeName</b></a> ( const QString & fileName )</li> +<li class=fn>QString <a href="#decodeName"><b>decodeName</b></a> ( const QCString & localFileName )</li> +<li class=fn>void <a href="#setEncodingFunction"><b>setEncodingFunction</b></a> ( EncoderFn f )</li> +<li class=fn>void <a href="#setDecodingFunction"><b>setDecodingFunction</b></a> ( DecoderFn f )</li> +<li class=fn>bool <a href="#exists"><b>exists</b></a> ( const QString & fileName )</li> +<li class=fn>bool <a href="#remove-2"><b>remove</b></a> ( const QString & fileName )</li> +</ul> +<h2>Important Inherited Members</h2> +<ul> +<li class=fn>virtual QByteArray <a href="#readAll"><b>readAll</b></a> ()</li> +</ul> +<h2>Protected Members</h2> +<ul> +<li class=fn>void <a href="#setErrorString"><b>setErrorString</b></a> ( const QString & str )</li> +</ul> +<hr><a name="details"></a><h2>Detailed Description</h2> + + + +The QFile class is an I/O device that operates on files. +<p> + +<p> QFile is an I/O device for reading and writing binary and text +files. A QFile may be used by itself or more conveniently with a +<a href="qdatastream.html">QDataStream</a> or <a href="qtextstream.html">QTextStream</a>. +<p> The file name is usually passed in the constructor but can be +changed with <a href="#setName">setName</a>(). You can check for a file's existence with +<a href="#exists">exists</a>() and remove a file with <a href="#remove">remove</a>(). +<p> The file is opened with <a href="#open">open</a>(), closed with <a href="#close">close</a>() and flushed +with <a href="#flush">flush</a>(). Data is usually read and written using QDataStream +or QTextStream, but you can read with <a href="qiodevice.html#readBlock">readBlock</a>() and <a href="#readLine">readLine</a>() +and write with <a href="qiodevice.html#writeBlock">writeBlock</a>(). QFile also supports <a href="#getch">getch</a>(), +<a href="#ungetch">ungetch</a>() and <a href="#putch">putch</a>(). +<p> The size of the file is returned by <a href="#size">size</a>(). You can get the +current file position or move to a new file position using the +<a href="qiodevice.html#at">at</a>() functions. If you've reached the end of the file, <a href="#atEnd">atEnd</a>() +returns TRUE. The file handle is returned by <a href="#handle">handle</a>(). +<p> Here is a code fragment that uses <a href="qtextstream.html">QTextStream</a> to read a text file +line by line. It prints each line with a line number. +<pre> + <a href="qstringlist.html">QStringList</a> lines; + QFile file( "file.txt" ); + if ( file.<a href="#open">open</a>( IO_ReadOnly ) ) { + <a href="qtextstream.html">QTextStream</a> stream( &file ); + <a href="qstring.html">QString</a> line; + int i = 1; + while ( !stream.<a href="qtextstream.html#atEnd">atEnd</a>() ) { + line = stream.<a href="qtextstream.html#readLine">readLine</a>(); // line of text excluding '\n' + printf( "%3d: %s\n", i++, line.<a href="qstring.html#latin1">latin1</a>() ); + lines += line; + } + file.<a href="#close">close</a>(); + } + </pre> + +<p> Writing text is just as easy. The following example shows how to +write the data we read into the string list from the previous +example: +<pre> + QFile file( "file.txt" ); + if ( file.<a href="#open">open</a>( IO_WriteOnly ) ) { + <a href="qtextstream.html">QTextStream</a> stream( &file ); + for ( QStringList::Iterator it = lines.begin(); it != lines.end(); ++it ) + stream << *it << "\n"; + file.<a href="#close">close</a>(); + } + </pre> + +<p> The <a href="qfileinfo.html">QFileInfo</a> class holds detailed information about a file, such +as access permissions, file dates and file types. +<p> The <a href="qdir.html">QDir</a> class manages directories and lists of file names. +<p> Qt uses Unicode file names. If you want to do your own I/O on Unix +systems you may want to use <a href="#encodeName">encodeName</a>() (and <a href="#decodeName">decodeName</a>()) to +convert the file name into the local encoding. +<p> +<p> <p>See also <a href="qdatastream.html">QDataStream</a>, <a href="qtextstream.html">QTextStream</a>, and <a href="io.html">Input/Output and Networking</a>. + +<hr><h2>Member Type Documentation</h2> +<h3 class=fn><a name="DecoderFn"></a>QFile::DecoderFn</h3> + +<p> This is used by <a href="#setDecodingFunction">QFile::setDecodingFunction</a>(). + +<h3 class=fn><a name="EncoderFn"></a>QFile::EncoderFn</h3> + +<p> This is used by <a href="#setEncodingFunction">QFile::setEncodingFunction</a>(). + +<hr><h2>Member Function Documentation</h2> +<h3 class=fn><a name="QFile"></a>QFile::QFile () +</h3> +Constructs a QFile with no name. + +<h3 class=fn><a name="QFile-2"></a>QFile::QFile ( const <a href="qstring.html">QString</a> & name ) +</h3> +Constructs a QFile with a file name <em>name</em>. +<p> <p>See also <a href="#setName">setName</a>(). + +<h3 class=fn><a name="~QFile"></a>QFile::~QFile () +</h3> +Destroys a QFile. Calls <a href="#close">close</a>(). + +<h3 class=fn>bool <a name="atEnd"></a>QFile::atEnd () const<tt> [virtual]</tt> +</h3> +Returns TRUE if the end of file has been reached; otherwise returns FALSE. +If QFile has not been <a href="#open">open</a>()'d, then the behavior is undefined. +<p> <p>See also <a href="#size">size</a>(). + +<p>Example: <a href="distributor-example.html#x2655">distributor/distributor.ui.h</a>. +<p>Reimplemented from <a href="qiodevice.html#atEnd">QIODevice</a>. +<h3 class=fn>void <a name="close"></a>QFile::close ()<tt> [virtual]</tt> +</h3> +Closes an open file. +<p> The file is not closed if it was opened with an existing file handle. +If the existing file handle is a <tt>FILE*</tt>, the file is flushed. +If the existing file handle is an <tt>int</tt> file descriptor, nothing +is done to the file. +<p> Some "write-behind" filesystems may report an unspecified error on +closing the file. These errors only indicate that something may +have gone wrong since the previous <a href="#open">open</a>(). In such a case <a href="qiodevice.html#status">status</a>() +reports <a href="qiodevice.html#status">IO_UnspecifiedError</a> after <a href="#close">close</a>(), otherwise <a href="qiodevice.html#status">IO_Ok</a>. +<p> <p>See also <a href="#open">open</a>() and <a href="#flush">flush</a>(). + +<p>Examples: <a href="tutorial2-07.html#x2590">chart/chartform_files.cpp</a>, <a href="distributor-example.html#x2656">distributor/distributor.ui.h</a>, <a href="helpviewer-example.html#x987">helpviewer/helpwindow.cpp</a>, <a href="mdi-example.html#x2023">mdi/application.cpp</a>, <a href="qdir-example.html#x1814">qdir/qdir.cpp</a>, <a href="qwerty-example.html#x362">qwerty/qwerty.cpp</a>, and <a href="outliner-example.html#x1914">xml/outliner/outlinetree.cpp</a>. +<p>Reimplemented from <a href="qiodevice.html#close">QIODevice</a>. +<h3 class=fn><a href="qstring.html">QString</a> <a name="decodeName"></a>QFile::decodeName ( const <a href="qcstring.html">QCString</a> & localFileName )<tt> [static]</tt> +</h3> +This does the reverse of <a href="#encodeName">QFile::encodeName</a>() using <em>localFileName</em>. +<p> <p>See also <a href="#setDecodingFunction">setDecodingFunction</a>(). + +<p>Example: <a href="distributor-example.html#x2657">distributor/distributor.ui.h</a>. +<h3 class=fn><a href="qcstring.html">QCString</a> <a name="encodeName"></a>QFile::encodeName ( const <a href="qstring.html">QString</a> & fileName )<tt> [static]</tt> +</h3> +When you use QFile, <a href="qfileinfo.html">QFileInfo</a>, and <a href="qdir.html">QDir</a> to access the file system +with Qt, you can use Unicode file names. On Unix, these file names +are converted to an 8-bit encoding. If you want to do your own +file I/O on Unix, you should convert the file name using this +function. On Windows NT/2000, Unicode file names are supported +directly in the file system and this function should be avoided. +On Windows 95, non-Latin1 locales are not supported. +<p> By default, this function converts <em>fileName</em> to the local 8-bit +encoding determined by the user's locale. This is sufficient for +file names that the user chooses. File names hard-coded into the +application should only use 7-bit ASCII filename characters. +<p> The conversion scheme can be changed using <a href="#setEncodingFunction">setEncodingFunction</a>(). +This might be useful if you wish to give the user an option to +store file names in UTF-8, etc., but be aware that such file names +would probably then be unrecognizable when seen by other programs. +<p> <p>See also <a href="#decodeName">decodeName</a>(). + +<p>Example: <a href="distributor-example.html#x2658">distributor/distributor.ui.h</a>. +<h3 class=fn><a href="qstring.html">QString</a> <a name="errorString"></a>QFile::errorString () const +</h3> +Returns a human-readable description of the reason of an error that occurred +on the device. The error described by the string corresponds to changes of +<a href="qiodevice.html#status">QIODevice::status</a>(). If the status is reset, the error string is also reset. +<p> The returned strings are not translated with the <a href="qobject.html#tr">QObject::tr</a>() or +<a href="qapplication.html#translate">QApplication::translate</a>() functions. They are marked as translatable +strings in the "QFile" context. Before you show the string to the user you +should translate it first, for example: +<p> <pre> + QFile f( "address.dat" ); + if ( !f.<a href="#open">open</a>( <a href="qfile.html#open">IO_ReadOnly</a> ) { + QMessageBox::<a href="qmessagebox.html#critical">critical</a>( + this, + tr("Open failed"), + tr("Could not open file for reading: %1").arg( qApp-><a href="qapplication.html#translate">translate</a>("QFile",f.<a href="#errorString">errorString</a>()) ) + ); + return; + } + </pre> + +<p> <p>See also <a href="qiodevice.html#status">QIODevice::status</a>(), <a href="qiodevice.html#resetStatus">QIODevice::resetStatus</a>(), and <a href="#setErrorString">setErrorString</a>(). + +<h3 class=fn>bool <a name="exists"></a>QFile::exists ( const <a href="qstring.html">QString</a> & fileName )<tt> [static]</tt> +</h3> +Returns TRUE if the file given by <em>fileName</em> exists; otherwise +returns FALSE. + +<p>Examples: <a href="tutorial2-05.html#x2563">chart/chartform.cpp</a>, <a href="dirview-example.html#x1674">dirview/dirview.cpp</a>, and <a href="helpviewer-example.html#x988">helpviewer/helpwindow.cpp</a>. +<h3 class=fn>bool <a name="exists-2"></a>QFile::exists () const +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Returns TRUE if this file exists; otherwise returns FALSE. +<p> <p>See also <a href="#name">name</a>(). + +<h3 class=fn>void <a name="flush"></a>QFile::flush ()<tt> [virtual]</tt> +</h3> +Flushes the file buffer to the disk. +<p> <a href="#close">close</a>() also flushes the file buffer. + +<p>Reimplemented from <a href="qiodevice.html#flush">QIODevice</a>. +<h3 class=fn>int <a name="getch"></a>QFile::getch ()<tt> [virtual]</tt> +</h3> +Reads a single byte/character from the file. +<p> Returns the byte/character read, or -1 if the end of the file has +been reached. +<p> <p>See also <a href="#putch">putch</a>() and <a href="#ungetch">ungetch</a>(). + +<p>Reimplemented from <a href="qiodevice.html#getch">QIODevice</a>. +<h3 class=fn>int <a name="handle"></a>QFile::handle () const +</h3> +Returns the file handle of the file. +<p> This is a small positive integer, suitable for use with C library +functions such as fdopen() and fcntl(). On systems that use file +descriptors for sockets (ie. Unix systems, but not Windows) the handle +can be used with <a href="qsocketnotifier.html">QSocketNotifier</a> as well. +<p> If the file is not open or there is an error, <a href="#handle">handle</a>() returns -1. +<p> <p>See also <a href="qsocketnotifier.html">QSocketNotifier</a>. + +<h3 class=fn><a href="qstring.html">QString</a> <a name="name"></a>QFile::name () const +</h3> + +<p> Returns the name set by <a href="#setName">setName</a>(). +<p> <p>See also <a href="#setName">setName</a>() and <a href="qfileinfo.html#fileName">QFileInfo::fileName</a>(). + +<h3 class=fn>bool <a name="open"></a>QFile::open ( int m )<tt> [virtual]</tt> +</h3> +Opens the file specified by the file name currently set, using the +mode <em>m</em>. Returns TRUE if successful, otherwise FALSE. +<p> <!-- index IO_Raw --><!-- index IO_ReadOnly --><!-- index IO_WriteOnly --><!-- index IO_ReadWrite --><!-- index IO_Append --><!-- index IO_Truncate --><!-- index IO_Translate --> +<p> The mode parameter <em>m</em> must be a combination of the following flags: +<center><table cellpadding="4" cellspacing="2" border="0"> +<tr bgcolor="#a2c511"> <th valign="top">Flag <th valign="top">Meaning +<tr bgcolor="#f0f0f0"> <td valign="top">IO_Raw +<td valign="top">Raw (non-buffered) file access. +<tr bgcolor="#d0d0d0"> <td valign="top">IO_ReadOnly +<td valign="top">Opens the file in read-only mode. +<tr bgcolor="#f0f0f0"> <td valign="top">IO_WriteOnly +<td valign="top">Opens the file in write-only mode. If this flag is used +with another flag, e.g. <a href="qfile.html#open">IO_ReadOnly</a> or <a href="qfile.html#open">IO_Raw</a> or <a href="qfile.html#open">IO_Append</a>, the file is <em>not</em> truncated; but if used on +its own (or with <a href="qfile.html#open">IO_Truncate</a>), the file is truncated. +<tr bgcolor="#d0d0d0"> <td valign="top">IO_ReadWrite +<td valign="top">Opens the file in read/write mode, equivalent to <tt>(IO_ReadOnly | IO_WriteOnly)</tt>. +<tr bgcolor="#f0f0f0"> <td valign="top">IO_Append +<td valign="top">Opens the file in append mode. (You must actually use <tt>(IO_WriteOnly | IO_Append)</tt> to make the file writable and +to go into append mode.) This mode is very useful when you +want to write something to a log file. The file index is +set to the end of the file. Note that the result is +undefined if you position the file index manually using +<a href="qiodevice.html#at">at</a>() in append mode. +<tr bgcolor="#d0d0d0"> <td valign="top">IO_Truncate +<td valign="top">Truncates the file. +<tr bgcolor="#f0f0f0"> <td valign="top">IO_Translate +<td valign="top">Enables carriage returns and linefeed translation for text +files under Windows. +</table></center> +<p> The raw access mode is best when I/O is block-operated using a 4KB +block size or greater. Buffered access works better when reading +small portions of data at a time. +<p> <b>Warning:</b> When working with buffered files, data may not be written +to the file at once. Call <a href="#flush">flush</a>() to make sure that the data is +really written. +<p> <b>Warning:</b> If you have a buffered file opened for both reading and +writing you must not perform an input operation immediately after +an output operation or vice versa. You should always call flush() +or a file positioning operation, e.g. at(), between input and +output operations, otherwise the buffer may contain garbage. +<p> If the file does not exist and <a href="qfile.html#open">IO_WriteOnly</a> or <a href="qfile.html#open">IO_ReadWrite</a> +is specified, it is created. +<p> Example: +<pre> + QFile f1( "/tmp/data.bin" ); + f1.<a href="#open">open</a>( IO_Raw | IO_ReadWrite ); + + QFile f2( "readme.txt" ); + f2.<a href="#open">open</a>( IO_ReadOnly | IO_Translate ); + + QFile f3( "audit.log" ); + f3.<a href="#open">open</a>( IO_WriteOnly | IO_Append ); + </pre> + +<p> <p>See also <a href="#name">name</a>(), <a href="#close">close</a>(), <a href="qiodevice.html#isOpen">isOpen</a>(), and <a href="#flush">flush</a>(). + +<p>Examples: <a href="simple-application-example.html#x1548">application/application.cpp</a>, <a href="tutorial2-07.html#x2591">chart/chartform_files.cpp</a>, <a href="distributor-example.html#x2659">distributor/distributor.ui.h</a>, <a href="helpviewer-example.html#x989">helpviewer/helpwindow.cpp</a>, <a href="qdir-example.html#x1815">qdir/qdir.cpp</a>, <a href="qwerty-example.html#x363">qwerty/qwerty.cpp</a>, and <a href="outliner-example.html#x1915">xml/outliner/outlinetree.cpp</a>. +<p>Reimplemented from <a href="qiodevice.html#open">QIODevice</a>. +<h3 class=fn>bool <a name="open-2"></a>QFile::open ( int m, FILE * f ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Opens a file in the mode <em>m</em> using an existing file handle <em>f</em>. +Returns TRUE if successful, otherwise FALSE. +<p> Example: +<pre> + #include <stdio.h> + + void printError( const char* msg ) + { + QFile f; + f.<a href="#open">open</a>( <a href="qfile.html#open">IO_WriteOnly</a>, stderr ); + f.<a href="qiodevice.html#writeBlock">writeBlock</a>( msg, qstrlen(msg) ); // write to stderr + f.<a href="#close">close</a>(); + } + </pre> + +<p> When a QFile is opened using this function, <a href="#close">close</a>() does not actually +close the file, only flushes it. +<p> <b>Warning:</b> If <em>f</em> is <tt>stdin</tt>, <tt>stdout</tt>, <tt>stderr</tt>, you may not +be able to seek. See <a href="qiodevice.html#isSequentialAccess">QIODevice::isSequentialAccess</a>() for more +information. +<p> <p>See also <a href="#close">close</a>(). + +<h3 class=fn>bool <a name="open-3"></a>QFile::open ( int m, int f ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Opens a file in the mode <em>m</em> using an existing file descriptor <em>f</em>. +Returns TRUE if successful, otherwise FALSE. +<p> When a QFile is opened using this function, <a href="#close">close</a>() does not actually +close the file. +<p> The QFile that is opened using this function, is automatically set to be in +raw mode; this means that the file input/output functions are slow. If you +run into performance issues, you should try to use one of the other open +functions. +<p> <b>Warning:</b> If <em>f</em> is one of 0 (stdin), 1 (stdout) or 2 (stderr), you may not +be able to seek. <a href="#size">size</a>() is set to <tt>INT_MAX</tt> (in limits.h). +<p> <p>See also <a href="#close">close</a>(). + +<h3 class=fn>int <a name="putch"></a>QFile::putch ( int ch )<tt> [virtual]</tt> +</h3> +Writes the character <em>ch</em> to the file. +<p> Returns <em>ch</em>, or -1 if some error occurred. +<p> <p>See also <a href="#getch">getch</a>() and <a href="#ungetch">ungetch</a>(). + +<p>Reimplemented from <a href="qiodevice.html#putch">QIODevice</a>. +<h3 class=fn><a href="qbytearray.html">QByteArray</a> <a name="readAll"></a>QIODevice::readAll ()<tt> [virtual]</tt> +</h3> +This convenience function returns all of the remaining data in the +device. + +<h3 class=fn>Q_LONG <a name="readLine"></a>QFile::readLine ( char * p, Q_ULONG maxlen )<tt> [virtual]</tt> +</h3> +Reads a line of text. +<p> Reads bytes from the file into the char* <em>p</em>, until end-of-line +or <em>maxlen</em> bytes have been read, whichever occurs first. Returns +the number of bytes read, or -1 if there was an error. Any +terminating newline is not stripped. +<p> This function is only efficient for buffered files. Avoid +<a href="#readLine">readLine</a>() for files that have been opened with the <a href="qfile.html#open">IO_Raw</a> +flag. +<p> <p>See also <a href="qiodevice.html#readBlock">readBlock</a>() and <a href="qtextstream.html#readLine">QTextStream::readLine</a>(). + +<p>Reimplemented from <a href="qiodevice.html#readLine">QIODevice</a>. +<h3 class=fn>Q_LONG <a name="readLine-2"></a>QFile::readLine ( <a href="qstring.html">QString</a> & s, Q_ULONG maxlen ) +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Reads a line of text. +<p> Reads bytes from the file into string <em>s</em>, until end-of-line or +<em>maxlen</em> bytes have been read, whichever occurs first. Returns +the number of bytes read, or -1 if there was an error, e.g. end of +file. Any terminating newline is not stripped. +<p> This function is only efficient for buffered files. Avoid using +<a href="#readLine">readLine</a>() for files that have been opened with the <a href="qfile.html#open">IO_Raw</a> +flag. +<p> Note that the string is read as plain Latin1 bytes, not Unicode. +<p> <p>See also <a href="qiodevice.html#readBlock">readBlock</a>() and <a href="qtextstream.html#readLine">QTextStream::readLine</a>(). + +<h3 class=fn>bool <a name="remove"></a>QFile::remove () +</h3> +Removes the file specified by the file name currently set. Returns +TRUE if successful; otherwise returns FALSE. +<p> The file is closed before it is removed. + +<h3 class=fn>bool <a name="remove-2"></a>QFile::remove ( const <a href="qstring.html">QString</a> & fileName )<tt> [static]</tt> +</h3> +This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +<p> Removes the file <em>fileName</em>. +Returns TRUE if successful, otherwise FALSE. + +<h3 class=fn>void <a name="setDecodingFunction"></a>QFile::setDecodingFunction ( <a href="qfile.html#DecoderFn">DecoderFn</a> f )<tt> [static]</tt> +</h3><p><b>Warning:</b> This function is <i>not</i> <a href="threads.html#reentrant">reentrant</a>.</p> + + +<p> Sets the function for decoding 8-bit file names to <em>f</em>. The +default uses the locale-specific 8-bit encoding. +<p> <p>See also <a href="#encodeName">encodeName</a>() and <a href="#decodeName">decodeName</a>(). + +<h3 class=fn>void <a name="setEncodingFunction"></a>QFile::setEncodingFunction ( <a href="qfile.html#EncoderFn">EncoderFn</a> f )<tt> [static]</tt> +</h3><p><b>Warning:</b> This function is <i>not</i> <a href="threads.html#reentrant">reentrant</a>.</p> + + +<p> Sets the function for encoding Unicode file names to <em>f</em>. The +default encodes in the locale-specific 8-bit encoding. +<p> <p>See also <a href="#encodeName">encodeName</a>(). + +<h3 class=fn>void <a name="setErrorString"></a>QFile::setErrorString ( const <a href="qstring.html">QString</a> & str )<tt> [protected]</tt> +</h3><p><b>Warning:</b> This function is <i>not</i> <a href="threads.html#reentrant">reentrant</a>.</p> + + +<p> Sets the error string returned by the <a href="#errorString">errorString</a>() function to <em>str</em>. +<p> <p>See also <a href="#errorString">errorString</a>() and <a href="qiodevice.html#status">QIODevice::status</a>(). + +<h3 class=fn>void <a name="setName"></a>QFile::setName ( const <a href="qstring.html">QString</a> & name ) +</h3> +Sets the name of the file to <em>name</em>. The name can have no path, a +relative path or an absolute absolute path. +<p> Do not call this function if the file has already been opened. +<p> If the file name has no path or a relative path, the path used +will be whatever the application's current directory path is +<em>at the time of the <a href="#open">open</a>()</em> call. +<p> Example: +<pre> + QFile file; + QDir::<a href="qdir.html#setCurrent">setCurrent</a>( "/tmp" ); + file.<a href="#setName">setName</a>( "readme.txt" ); + QDir::<a href="qdir.html#setCurrent">setCurrent</a>( "/home" ); + file.<a href="#open">open</a>( <a href="qfile.html#open">IO_ReadOnly</a> ); // opens "/home/readme.txt" under Unix + </pre> + +<p> Note that the directory separator "/" works for all operating +systems supported by Qt. +<p> <p>See also <a href="#name">name</a>(), <a href="qfileinfo.html">QFileInfo</a>, and <a href="qdir.html">QDir</a>. + +<h3 class=fn><a href="qiodevice.html#Offset">Offset</a> <a name="size"></a>QFile::size () const<tt> [virtual]</tt> +</h3> +Returns the file size. +<p>See also <a href="qiodevice.html#at">at</a>(). + +<p>Example: <a href="statistics-example.html#x2781">table/statistics/statistics.cpp</a>. +<p>Reimplemented from <a href="qiodevice.html#size">QIODevice</a>. +<h3 class=fn>int <a name="ungetch"></a>QFile::ungetch ( int ch )<tt> [virtual]</tt> +</h3> +Puts the character <em>ch</em> back into the file and decrements the +index if it is not zero. +<p> This function is normally called to "undo" a <a href="#getch">getch</a>() operation. +<p> Returns <em>ch</em>, or -1 if an error occurred. +<p> <p>See also <a href="#getch">getch</a>() and <a href="#putch">putch</a>(). + +<p>Reimplemented from <a href="qiodevice.html#ungetch">QIODevice</a>. +<!-- eof --> +<hr><p> +This file is part of the <a href="index.html">Qt toolkit</a>. +Copyright © 1995-2007 +<a href="http://www.trolltech.com/">Trolltech</a>. All Rights Reserved.<p><address><hr><div align=center> +<table width=100% cellspacing=0 border=0><tr> +<td>Copyright © 2007 +<a href="troll.html">Trolltech</a><td align=center><a href="trademarks.html">Trademarks</a> +<td align=right><div align=right>Qt 3.3.8</div> +</table></div></address></body> +</html> |