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%% Purpose: wxFFile documentation
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%% Author: Vadim Zeitlin
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%% Created: 14.01.02 (extracted from file.tex)
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%% RCS-ID: $Id: ffile.tex,v 1.14 2005/04/08 14:33:32 MW Exp $
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%% Copyright: (c) Vadim Zeitlin
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%% License: wxWindows license
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%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
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\section{\class{wxFFile}}\label{wxffile}
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wxFFile implements buffered file I/O. This is a very small class designed to
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minimize the overhead of using it - in fact, there is hardly any overhead at
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all, but using it brings you automatic error checking and hides differences
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between platforms and compilers. It wraps inside it a {\tt FILE *} handle used
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by standard C IO library (also known as {\tt stdio}).
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\wxheading{Derived from}
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\wxheading{Include files}
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\begin{twocollist}\itemsep=0pt%
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\twocolitem{{\bf wxFromStart}}{Count offset from the start of the file}
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\twocolitem{{\bf wxFromCurrent}}{Count offset from the current position of the file pointer}
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\twocolitem{{\bf wxFromEnd}}{Count offset from the end of the file (backwards)}
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\latexignore{\rtfignore{\wxheading{Members}}}
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\membersection{wxFFile::wxFFile}\label{wxffilector}
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\func{}{wxFFile}{\void}
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\func{}{wxFFile}{\param{const char*}{ filename}, \param{const char*}{ mode = "r"}}
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Opens a file with the given mode. As there is no way to return whether the
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operation was successful or not from the constructor you should test the
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return value of \helpref{IsOpened}{wxffileisopened} to check that it didn't
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\func{}{wxFFile}{\param{FILE*}{ fp}}
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Opens a file with the given file pointer, which has already been opened.
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\wxheading{Parameters}
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\docparam{filename}{The filename.}
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\docparam{mode}{The mode in which to open the file using standard C strings.
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Note that you should use {\tt "b"} flag if you use binary files under Windows
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or the results might be unexpected due to automatic newline conversion done
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\docparam{fp}{An existing file descriptor, such as stderr.}
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\membersection{wxFFile::\destruct{wxFFile}}\label{wxffiledtor}
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\func{}{\destruct{wxFFile}}{\void}
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Destructor will close the file.
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NB: it is not virtual so you should {\it not} derive from wxFFile!
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\membersection{wxFFile::Attach}\label{wxffileattach}
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\func{void}{Attach}{\param{FILE*}{ fp}}
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Attaches an existing file pointer to the wxFFile object.
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The descriptor should be already opened and it will be closed by wxFFile
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\membersection{wxFFile::Close}\label{wxffileclose}
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\func{bool}{Close}{\void}
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Closes the file and returns \true on success.
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\membersection{wxFFile::Detach}\label{wxffiledetach}
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\func{void}{Detach}{\void}
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Get back a file pointer from wxFFile object -- the caller is responsible for closing the file if this
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descriptor is opened. \helpref{IsOpened()}{wxffileisopened} will return \false after call to Detach().
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\membersection{wxFFile::fp}\label{wxffilefp}
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\constfunc{FILE *}{fp}{\void}
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Returns the file pointer associated with the file.
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\membersection{wxFFile::Eof}\label{wxffileeof}
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\constfunc{bool}{Eof}{\void}
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Returns \true if the an attempt has been made to read {\it past}
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Note that the behaviour of the file descriptor based class
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\helpref{wxFile}{wxfile} is different as \helpref{wxFile::Eof}{wxfileeof}
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will return \true here as soon as the last byte of the file has been
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Also note that this method may only be called for opened files and may crash if
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the file is not opened.
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\helpref{IsOpened}{wxffileisopened}
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\membersection{wxFFile::Error}\label{wxffileerror}
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Returns \true if an error has occurred on this file, similar to the standard
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\texttt{ferror()} function.
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Please note that this method may only be called for opened files and may crash
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if the file is not opened.
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\helpref{IsOpened}{wxffileisopened}
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\membersection{wxFFile::Flush}\label{wxffileflush}
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\func{bool}{Flush}{\void}
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Flushes the file and returns \true on success.
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\membersection{wxFFile::GetKind}\label{wxffilegetfilekind}
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\constfunc{wxFileKind}{GetKind}{\void}
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Returns the type of the file. Possible return values are:
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wxFILE_KIND_DISK, // a file supporting seeking to arbitrary offsets
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wxFILE_KIND_TERMINAL, // a tty
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wxFILE_KIND_PIPE // a pipe
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\membersection{wxFFile::IsOpened}\label{wxffileisopened}
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\constfunc{bool}{IsOpened}{\void}
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Returns \true if the file is opened. Most of the methods of this class may only
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be used for an opened file.
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\membersection{wxFFile::Length}\label{wxffilelength}
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\constfunc{wxFileOffset}{Length}{\void}
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Returns the length of the file.
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\membersection{wxFFile::Open}\label{wxffileopen}
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\func{bool}{Open}{\param{const char*}{ filename}, \param{const char*}{ mode = "r"}}
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Opens the file, returning \true if successful.
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\wxheading{Parameters}
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\docparam{filename}{The filename.}
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\docparam{mode}{The mode in which to open the file.}
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\membersection{wxFFile::Read}\label{wxffileread}
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\func{size\_t}{Read}{\param{void*}{ buffer}, \param{size\_t}{ count}}
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Reads the specified number of bytes into a buffer, returning the actual number read.
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\wxheading{Parameters}
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\docparam{buffer}{A buffer to receive the data.}
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\docparam{count}{The number of bytes to read.}
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\wxheading{Return value}
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The number of bytes read.
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\membersection{wxFFile::ReadAll}\label{wxffilereadall}
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\func{bool}{ReadAll}{\param{wxString *}{ str}, \param{wxMBConv\&}{ conv = wxConvUTF8}}
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Reads the entire contents of the file into a string.
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\wxheading{Parameters}
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\docparam{str}{String to read data into.}
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\docparam{conv}{Conversion object to use in Unicode build; by default supposes
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that file contents is encoded in UTF-8.}
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\wxheading{Return value}
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\true if file was read successfully, \false otherwise.
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\membersection{wxFFile::Seek}\label{wxffileseek}
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\func{bool}{Seek}{\param{wxFileOffset }{ofs}, \param{wxSeekMode }{mode = wxFromStart}}
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Seeks to the specified position and returns \true on success.
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\wxheading{Parameters}
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\docparam{ofs}{Offset to seek to.}
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\docparam{mode}{One of {\bf wxFromStart}, {\bf wxFromEnd}, {\bf wxFromCurrent}.}
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\membersection{wxFFile::SeekEnd}\label{wxffileseekend}
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\func{bool}{SeekEnd}{\param{wxFileOffset }{ofs = 0}}
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Moves the file pointer to the specified number of bytes before the end of the file
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and returns \true on success.
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\wxheading{Parameters}
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\docparam{ofs}{Number of bytes before the end of the file.}
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\membersection{wxFFile::Tell}\label{wxffiletell}
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\constfunc{wxFileOffset}{Tell}{\void}
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Returns the current position.
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\membersection{wxFFile::Write}\label{wxffilewrite}
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\func{size\_t}{Write}{\param{const void*}{ buffer}, \param{size\_t}{ count}}
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Writes the specified number of bytes from a buffer.
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\wxheading{Parameters}
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\docparam{buffer}{A buffer containing the data.}
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\docparam{count}{The number of bytes to write.}
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\wxheading{Return value}
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Number of bytes written.
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\membersection{wxFFile::Write}\label{wxffilewrites}
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\func{bool}{Write}{\param{const wxString\& }{s}, \param{wxMBConv\&}{ conv = wxConvUTF8}}
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Writes the contents of the string to the file, returns \true on success.
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The second argument is only meaningful in Unicode build of wxWidgets when
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{\it conv} is used to convert {\it s} to multibyte representation.