From 252a2ec8b0f0f9cf20c947737087b24a8185b588 Mon Sep 17 00:00:00 2001 From: Michele Calgaro Date: Wed, 10 Jul 2024 18:56:16 +0900 Subject: Rename IO and network class nt* related files to equivalent tq* Signed-off-by: Michele Calgaro --- doc/html/tqfile.html | 503 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 503 insertions(+) create mode 100644 doc/html/tqfile.html (limited to 'doc/html/tqfile.html') diff --git a/doc/html/tqfile.html b/doc/html/tqfile.html new file mode 100644 index 000000000..2dc549dfb --- /dev/null +++ b/doc/html/tqfile.html @@ -0,0 +1,503 @@ + + + + + +TQFile Class + + + + + + + +
+ +Home + | +All Classes + | +Main Classes + | +Annotated + | +Grouped Classes + | +Functions +

TQFile Class Reference

+ +

The TQFile class is an I/O device that operates on files. +More... +

Almost all the functions in this class are reentrant when TQt is built with thread support. The exceptions are setEncodingFunction(), setDecodingFunction(), and setErrorString(). +

#include <tqfile.h> +

Inherits TQIODevice. +

List of all member functions. +

Public Members

+ +

Static Public Members

+ +

Important Inherited Members

+ +

Protected Members

+ +

Detailed Description

+ + + +The TQFile class is an I/O device that operates on files. +

+ +

TQFile is an I/O device for reading and writing binary and text +files. A TQFile may be used by itself or more conveniently with a +TQDataStream or TQTextStream. +

The file name is usually passed in the constructor but can be +changed with setName(). You can check for a file's existence with +exists() and remove a file with remove(). +

The file is opened with open(), closed with close() and flushed +with flush(). Data is usually read and written using TQDataStream +or TQTextStream, but you can read with readBlock() and readLine() +and write with writeBlock(). TQFile also supports getch(), +ungetch() and putch(). +

The size of the file is returned by size(). You can get the +current file position or move to a new file position using the +at() functions. If you've reached the end of the file, atEnd() +returns TRUE. The file handle is returned by handle(). +

Here is a code fragment that uses TQTextStream to read a text file +line by line. It prints each line with a line number. +

+    TQStringList lines;
+    TQFile file( "file.txt" );
+    if ( file.open( IO_ReadOnly ) ) {
+        TQTextStream stream( &file );
+        TQString line;
+        int i = 1;
+        while ( !stream.atEnd() ) {
+            line = stream.readLine(); // line of text excluding '\n'
+            printf( "%3d: %s\n", i++, line.latin1() );
+            lines += line;
+        }
+        file.close();
+    }
+
+ +

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: +

+    TQFile file( "file.txt" );
+    if ( file.open( IO_WriteOnly ) ) {
+        TQTextStream stream( &file );
+        for ( TQStringList::Iterator it = lines.begin(); it != lines.end(); ++it )
+            stream << *it << "\n";
+        file.close();
+    }
+
+ +

The TQFileInfo class holds detailed information about a file, such +as access permissions, file dates and file types. +

The TQDir class manages directories and lists of file names. +

TQt uses Unicode file names. If you want to do your own I/O on Unix +systems you may want to use encodeName() (and decodeName()) to +convert the file name into the local encoding. +

+

See also TQDataStream, TQTextStream, and Input/Output and Networking. + +

Member Type Documentation

+

TQFile::DecoderFn

+ +

This is used by TQFile::setDecodingFunction(). + +

TQFile::EncoderFn

+ +

This is used by TQFile::setEncodingFunction(). + +

Member Function Documentation

+

TQFile::TQFile () +

+Constructs a TQFile with no name. + +

TQFile::TQFile ( const TQString & name ) +

+Constructs a TQFile with a file name name. +

See also setName(). + +

TQFile::~TQFile () +

+Destroys a TQFile. Calls close(). + +

bool TQFile::atEnd () const [virtual] +

+Returns TRUE if the end of file has been reached; otherwise returns FALSE. +If TQFile has not been open()'d, then the behavior is undefined. +

See also size(). + +

Example: distributor/distributor.ui.h. +

Reimplemented from TQIODevice. +

void TQFile::close () [virtual] +

+Closes an open file. +

The file is not closed if it was opened with an existing file handle. +If the existing file handle is a FILE*, the file is flushed. +If the existing file handle is an int file descriptor, nothing +is done to the file. +

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 open(). In such a case status() +reports IO_UnspecifiedError after close(), otherwise IO_Ok. +

See also open() and flush(). + +

Examples: chart/chartform_files.cpp, distributor/distributor.ui.h, helpviewer/helpwindow.cpp, mdi/application.cpp, tqdir/tqdir.cpp, qwerty/qwerty.cpp, and xml/outliner/outlinetree.cpp. +

Reimplemented from TQIODevice. +

TQString TQFile::decodeName ( const TQCString & localFileName ) [static] +

+This does the reverse of TQFile::encodeName() using localFileName. +

See also setDecodingFunction(). + +

Example: distributor/distributor.ui.h. +

TQCString TQFile::encodeName ( const TQString & fileName ) [static] +

+When you use TQFile, TQFileInfo, and TQDir to access the file system +with TQt, 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. +

By default, this function converts fileName 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. +

The conversion scheme can be changed using setEncodingFunction(). +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. +

See also decodeName(). + +

Example: distributor/distributor.ui.h. +

TQString TQFile::errorString () const +

+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 +TQIODevice::status(). If the status is reset, the error string is also reset. +

The returned strings are not translated with the TQObject::tr() or +TQApplication::translate() functions. They are marked as translatable +strings in the "TQFile" context. Before you show the string to the user you +should translate it first, for example: +

+        TQFile f( "address.dat" );
+        if ( !f.open( IO_ReadOnly ) {
+            TQMessageBox::critical(
+                this,
+                tr("Open failed"),
+                tr("Could not open file for reading: %1").arg( tqApp->translate("TQFile",f.errorString()) )
+                );
+            return;
+        }
+
+ +

See also TQIODevice::status(), TQIODevice::resetStatus(), and setErrorString(). + +

bool TQFile::exists ( const TQString & fileName ) [static] +

+Returns TRUE if the file given by fileName exists; otherwise +returns FALSE. + +

Examples: chart/chartform.cpp, dirview/dirview.cpp, and helpviewer/helpwindow.cpp. +

bool TQFile::exists () const +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +

Returns TRUE if this file exists; otherwise returns FALSE. +

See also name(). + +

void TQFile::flush () [virtual] +

+Flushes the file buffer to the disk. +

close() also flushes the file buffer. + +

Reimplemented from TQIODevice. +

int TQFile::getch () [virtual] +

+Reads a single byte/character from the file. +

Returns the byte/character read, or -1 if the end of the file has +been reached. +

See also putch() and ungetch(). + +

Reimplemented from TQIODevice. +

int TQFile::handle () const +

+Returns the file handle of the file. +

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 TQSocketNotifier as well. +

If the file is not open or there is an error, handle() returns -1. +

See also TQSocketNotifier. + +

TQString TQFile::name () const +

+ +

Returns the name set by setName(). +

See also setName() and TQFileInfo::fileName(). + +

bool TQFile::open ( int m ) [virtual] +

+Opens the file specified by the file name currently set, using the +mode m. Returns TRUE if successful, otherwise FALSE. +

+

The mode parameter m must be a combination of the following flags: +

+
Flag Meaning +
IO_Raw +Raw (non-buffered) file access. +
IO_ReadOnly +Opens the file in read-only mode. +
IO_WriteOnly +Opens the file in write-only mode. If this flag is used +with another flag, e.g. IO_ReadOnly or IO_Raw or IO_Append, the file is not truncated; but if used on +its own (or with IO_Truncate), the file is truncated. +
IO_ReadWrite +Opens the file in read/write mode, equivalent to (IO_ReadOnly | IO_WriteOnly). +
IO_Append +Opens the file in append mode. (You must actually use (IO_WriteOnly | IO_Append) 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 +at() in append mode. +
IO_Truncate +Truncates the file. +
IO_Translate +Enables carriage returns and linefeed translation for text +files under Windows. +
+

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. +

Warning: When working with buffered files, data may not be written +to the file at once. Call flush() to make sure that the data is +really written. +

Warning: 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. +

If the file does not exist and IO_WriteOnly or IO_ReadWrite +is specified, it is created. +

Example: +

+        TQFile f1( "/tmp/data.bin" );
+        f1.open( IO_Raw | IO_ReadWrite );
+
+        TQFile f2( "readme.txt" );
+        f2.open( IO_ReadOnly | IO_Translate );
+
+        TQFile f3( "audit.log" );
+        f3.open( IO_WriteOnly | IO_Append );
+
+ +

See also name(), close(), isOpen(), and flush(). + +

Examples: application/application.cpp, chart/chartform_files.cpp, distributor/distributor.ui.h, helpviewer/helpwindow.cpp, tqdir/tqdir.cpp, qwerty/qwerty.cpp, and xml/outliner/outlinetree.cpp. +

Reimplemented from TQIODevice. +

bool TQFile::open ( int m, FILE * f ) +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +

Opens a file in the mode m using an existing file handle f. +Returns TRUE if successful, otherwise FALSE. +

Example: +

+    #include <stdio.h>
+
+    void printError( const char* msg )
+    {
+        TQFile f;
+        f.open( IO_WriteOnly, stderr );
+        f.writeBlock( msg, tqstrlen(msg) );      // write to stderr
+        f.close();
+    }
+
+ +

When a TQFile is opened using this function, close() does not actually +close the file, only flushes it. +

Warning: If f is stdin, stdout, stderr, you may not +be able to seek. See TQIODevice::isSequentialAccess() for more +information. +

See also close(). + +

bool TQFile::open ( int m, int f ) +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +

Opens a file in the mode m using an existing file descriptor f. +Returns TRUE if successful, otherwise FALSE. +

When a TQFile is opened using this function, close() does not actually +close the file. +

The TQFile 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. +

Warning: If f is one of 0 (stdin), 1 (stdout) or 2 (stderr), you may not +be able to seek. size() is set to INT_MAX (in limits.h). +

See also close(). + +

int TQFile::putch ( int ch ) [virtual] +

+Writes the character ch to the file. +

Returns ch, or -1 if some error occurred. +

See also getch() and ungetch(). + +

Reimplemented from TQIODevice. +

TQByteArray TQIODevice::readAll () [virtual] +

+This convenience function returns all of the remaining data in the +device. + +

TQ_LONG TQFile::readLine ( char * p, TQ_ULONG maxlen ) [virtual] +

+Reads a line of text. +

Reads bytes from the file into the char* p, until end-of-line +or maxlen 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. +

This function is only efficient for buffered files. Avoid +readLine() for files that have been opened with the IO_Raw +flag. +

See also readBlock() and TQTextStream::readLine(). + +

Reimplemented from TQIODevice. +

TQ_LONG TQFile::readLine ( TQString & s, TQ_ULONG maxlen ) +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +

Reads a line of text. +

Reads bytes from the file into string s, until end-of-line or +maxlen 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. +

This function is only efficient for buffered files. Avoid using +readLine() for files that have been opened with the IO_Raw +flag. +

Note that the string is read as plain Latin1 bytes, not Unicode. +

See also readBlock() and TQTextStream::readLine(). + +

bool TQFile::remove () +

+Removes the file specified by the file name currently set. Returns +TRUE if successful; otherwise returns FALSE. +

The file is closed before it is removed. + +

bool TQFile::remove ( const TQString & fileName ) [static] +

+This is an overloaded member function, provided for convenience. It behaves essentially like the above function. +

Removes the file fileName. +Returns TRUE if successful, otherwise FALSE. + +

void TQFile::setDecodingFunction ( DecoderFn f ) [static] +

Warning: This function is not reentrant.

+ + +

Sets the function for decoding 8-bit file names to f. The +default uses the locale-specific 8-bit encoding. +

See also encodeName() and decodeName(). + +

void TQFile::setEncodingFunction ( EncoderFn f ) [static] +

Warning: This function is not reentrant.

+ + +

Sets the function for encoding Unicode file names to f. The +default encodes in the locale-specific 8-bit encoding. +

See also encodeName(). + +

void TQFile::setErrorString ( const TQString & str ) [protected] +

Warning: This function is not reentrant.

+ + +

Sets the error string returned by the errorString() function to str. +

See also errorString() and TQIODevice::status(). + +

void TQFile::setName ( const TQString & name ) +

+Sets the name of the file to name. The name can have no path, a +relative path or an absolute absolute path. +

Do not call this function if the file has already been opened. +

If the file name has no path or a relative path, the path used +will be whatever the application's current directory path is +at the time of the open() call. +

Example: +

+        TQFile file;
+        TQDir::setCurrent( "/tmp" );
+        file.setName( "readme.txt" );
+        TQDir::setCurrent( "/home" );
+        file.open( IO_ReadOnly );      // opens "/home/readme.txt" under Unix
+
+ +

Note that the directory separator "/" works for all operating +systems supported by TQt. +

See also name(), TQFileInfo, and TQDir. + +

Offset TQFile::size () const [virtual] +

+Returns the file size. +

See also at(). + +

Example: table/statistics/statistics.cpp. +

Reimplemented from TQIODevice. +

int TQFile::ungetch ( int ch ) [virtual] +

+Puts the character ch back into the file and decrements the +index if it is not zero. +

This function is normally called to "undo" a getch() operation. +

Returns ch, or -1 if an error occurred. +

See also getch() and putch(). + +

Reimplemented from TQIODevice. + +

+This file is part of the TQt toolkit. +Copyright © 1995-2007 +Trolltech. All Rights Reserved.

+ +
Copyright © 2007 +TrolltechTrademarks +
TQt 3.3.8
+
+ -- cgit v1.2.1