X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/954b8ae60391d18b87a604e7919c87c0c6ae208b..d80cd92ae2d648a9a11707502277e5c79f5f65b7:/docs/latex/wx/file.tex?ds=inline diff --git a/docs/latex/wx/file.tex b/docs/latex/wx/file.tex index 573407deed..8d799e648c 100644 --- a/docs/latex/wx/file.tex +++ b/docs/latex/wx/file.tex @@ -3,7 +3,8 @@ A wxFile performs raw file I/O. This is a very small class designed to minimize the overhead of using it - in fact, there is hardly any overhead at all, but using it brings you automatic error checking and hides differences -between platforms and compilers. +between platforms and compilers. wxFile also automatically closes the file in +its destructor making it unnecessary to worry about forgetting to do it. \wxheading{Derived from} @@ -82,7 +83,7 @@ fail. \func{}{wxFile}{\param{int}{ fd}} -Opens a file with the given file descriptor, which has already been opened. +Associates the file with the given file descriptor, which has already been opened. \wxheading{Parameters} @@ -98,7 +99,7 @@ Opens a file with the given file descriptor, which has already been opened. Destructor will close the file. -NB: it is not virtual so you should {\it not} derive from wxFile! +NB: it is not virtual so you should use wxFile polymorphically. \membersection{wxFile::Access}\label{wxfileaccess} @@ -113,7 +114,7 @@ values of wxFile::read or wxFile::write really make sense here. Attaches an existing file descriptor to the wxFile object. Example of predefined file descriptors are 0, 1 and 2 which correspond to stdin, stdout and stderr (and -have symbolic names of wxFile::fd\_stdin, wxFile::fd\_stdout and wxFile::fd\_stderr). +have symbolic names of {\bf wxFile::fd\_stdin}, {\bf wxFile::fd\_stdout} and {\bf wxFile::fd\_stderr}). The descriptor should be already opened and it will be closed by wxFile object. @@ -150,11 +151,23 @@ Returns the file descriptor associated with the file. Returns TRUE if the end of the file has been reached. +Note that the behaviour of the file pointer based class +\helpref{wxFFile}{wxffile} is different as \helpref{wxFFile::Eof}{wxffileeof} +will return TRUE here only if an attempt has been made to read +{\it past} the last byte of the file, while wxFile::Eof() will return TRUE +even before such attempt is made if the file pointer is at the last position +in the file. + +Note also that this function doesn't work on unseekable file descriptors +(examples include pipes, terminals and sockets under Unix) and an attempt to +use it will result in an error message in such case. + \membersection{wxFile::Exists}\label{wxfileexists} \func{static bool}{Exists}{\param{const char*}{ filename}} -Returns TRUE if the given name specifies an existing regular file. +Returns TRUE if the given name specifies an existing regular file (not a +directory or a link) \membersection{wxFile::Flush}\label{wxfileflush} @@ -208,7 +221,7 @@ The number of bytes read, or the symbol {\bf wxInvalidOffset} (-1) if there was \membersection{wxFile::Seek}\label{wxfileseek} -\func{off\_t}{Seek}{\param{off\_t }{ofs}, \param{wxFile::SeekMode }{mode = wxFile::FromStart}} +\func{off\_t}{Seek}{\param{off\_t }{ofs}, \param{wxSeekMode }{mode = wxFromStart}} Seeks to the specified position. @@ -216,7 +229,7 @@ Seeks to the specified position. \docparam{ofs}{Offset to seek to.} -\docparam{mode}{One of {\bf wxFile::FromStart}, {\bf wxFile::FromEnd}, {\bf wxFile::FromCurrent}.} +\docparam{mode}{One of {\bf wxFromStart}, {\bf wxFromEnd}, {\bf wxFromCurrent}.} \wxheading{Return value} @@ -261,7 +274,201 @@ TRUE if the operation was successful. \membersection{wxFile::Write}\label{wxfilewrites} -\func{bool}{Write}{\param{const wxString& }{s}} +\func{bool}{Write}{\param{const wxString\& }{s}} + +Writes the contents of the string to the file, returns TRUE on success. + +\section{\class{wxFFile}}\label{wxffile} + +A wxFFile performs raw file I/O. This is a very small class designed to +minimize the overhead of using it - in fact, there is hardly any overhead at +all, but using it brings you automatic error checking and hides differences +between platforms and compilers. + +\wxheading{Derived from} + +None. + +\wxheading{Include files} + + + +\twocolwidtha{7cm} +\begin{twocollist}\itemsep=0pt% +\twocolitem{{\bf wxFromStart}}{Count offset from the start of the file} +\twocolitem{{\bf wxFromCurrent}}{Count offset from the current position of the file pointer} +\twocolitem{{\bf wxFromEnd}}{Count offset from the end of the file (backwards)} +\end{twocollist} + +\latexignore{\rtfignore{\wxheading{Members}}} + +\membersection{wxFFile::wxFFile}\label{wxffileconstr} + +\func{}{wxFFile}{\void} + +Default constructor. + +\func{}{wxFFile}{\param{const char*}{ filename}, \param{const char*}{ mode = "r"}} + +Opens a file with the given mode. As there is no way to return whether the +operation was successful or not from the constructor you should test the +return value of \helpref{IsOpened}{wxffileisopened} to check that it didn't +fail. + +\func{}{wxFFile}{\param{FILE*}{ fp}} + +Opens a file with the given file pointer, which has already been opened. + +\wxheading{Parameters} + +\docparam{filename}{The filename.} + +\docparam{mode}{The mode in which to open the file using standard C strings.} + +\docparam{fp}{An existing file descriptor, such as stderr.} + +\membersection{wxFFile::\destruct{wxFFile}} + +\func{}{\destruct{wxFFile}}{\void} + +Destructor will close the file. + +NB: it is not virtual so you should {\it not} derive from wxFFile! + +\membersection{wxFFile::Attach}\label{wxffileattach} + +\func{void}{Attach}{\param{FILE*}{ fp}} + +Attaches an existing file pointer to the wxFFile object. + +The descriptor should be already opened and it will be closed by wxFFile +object. + +\membersection{wxFFile::Close}\label{wxffileclose} + +\func{bool}{Close}{\void} + +Closes the file and returns TRUE on success. + +\membersection{wxFFile::Detach}\label{wxffiledetach} + +\func{void}{Detach}{\void} + +Get back a file pointer from wxFFile object - the caller is responsible for closing the file if this +descriptor is opened. \helpref{IsOpened()}{wxffileisopened} will return FALSE after call to Detach(). + +\membersection{wxFFile::fp}\label{wxffilefp} + +\constfunc{FILE *}{fp}{\void} + +Returns the file pointer associated with the file. + +\membersection{wxFFile::Eof}\label{wxffileeof} + +\constfunc{bool}{Eof}{\void} + +Returns TRUE if the an attempt has been made to read {\it past} +the end of the file. + +Note that the behaviour of the file descriptor based class +\helpref{wxFile}{wxfile} is different as \helpref{wxFile::Eof}{wxfileeof} +will return TRUE here as soon as the last byte of the file has been +read. + +\membersection{wxFFile::Flush}\label{wxffileflush} + +\func{bool}{Flush}{\void} + +Flushes the file and returns TRUE on success. + +\membersection{wxFFile::IsOpened}\label{wxffileisopened} + +\constfunc{bool}{IsOpened}{\void} + +Returns TRUE if the file has been opened. + +\membersection{wxFFile::Length}\label{wxffilelength} + +\constfunc{size\_t}{Length}{\void} + +Returns the length of the file. + +\membersection{wxFFile::Open}\label{wxffileopen} + +\func{bool}{Open}{\param{const char*}{ filename}, \param{const char*}{ mode = "r"}} + +Opens the file, returning TRUE if successful. + +\wxheading{Parameters} + +\docparam{filename}{The filename.} + +\docparam{mode}{The mode in which to open the file.} + +\membersection{wxFFile::Read}\label{wxffileread} + +\func{size\_t}{Read}{\param{void*}{ buffer}, \param{off\_t}{ count}} + +Reads the specified number of bytes into a buffer, returning the actual number read. + +\wxheading{Parameters} + +\docparam{buffer}{A buffer to receive the data.} + +\docparam{count}{The number of bytes to read.} + +\wxheading{Return value} + +The number of bytes read. + +\membersection{wxFFile::Seek}\label{wxffileseek} + +\func{bool}{Seek}{\param{long }{ofs}, \param{wxSeekMode }{mode = wxFromStart}} + +Seeks to the specified position and returs TRUE on success. + +\wxheading{Parameters} + +\docparam{ofs}{Offset to seek to.} + +\docparam{mode}{One of {\bf wxFromStart}, {\bf wxFromEnd}, {\bf wxFromCurrent}.} + +\membersection{wxFFile::SeekEnd}\label{wxffileseekend} + +\func{bool}{SeekEnd}{\param{long }{ofs = 0}} + +Moves the file pointer to the specified number of bytes before the end of the file +and returns TRUE on success. + +\wxheading{Parameters} + +\docparam{ofs}{Number of bytes before the end of the file.} + +\membersection{wxFFile::Tell}\label{wxffiletell} + +\constfunc{size\_t}{Tell}{\void} + +Returns the current position. + +\membersection{wxFFile::Write}\label{wxffilewrite} + +\func{size\_t}{Write}{\param{const void*}{ buffer}, \param{size\_t}{ count}} + +Writes the specified number of bytes from a buffer. + +\wxheading{Parameters} + +\docparam{buffer}{A buffer containing the data.} + +\docparam{count}{The number of bytes to write.} + +\wxheading{Return value} + +Number of bytes written. + +\membersection{wxFFile::Write}\label{wxffilewrites} + +\func{bool}{Write}{\param{const wxString\& }{s}} Writes the contents of the string to the file, returns TRUE on success.