Tools.h++ Manual

21-110 104011 Tandem Computers Incorporated
21
RWFile
Synopsis #include <rw/rwfile.h>
RWFile f("filename");
Description Class RWFile encapsulates binary file operations using the Standard C stream
library (functions fopen(), fread(), fwrite(), etc.). This class is based
on class PFile of the Interviews Class Library (1987, Stanford University). The
member function names begin with upper case letters in order to maintain
compatibility with class PFile .
Because this class is intended to encapsulate binary operations, it is important
that it be opened using a binary mode. This is particularly important under
MS-DOS—otherwise bytes that happen to match a newline will be expanded to
(carriage return, line feed).
Public constructors RWFile(const char* filename, const char* mode = 0);
Construct an RWFile to be used with the file of name filename and with
mode mode . The mode is as given by the Standard C library function
fopen() . If mode is zero (the default) then the constructor will attempt to
open an existing file with the given filename for update (mode " rb+ "). If this is
not possible, then it will attempt to create a new file with the given filename
(mode " wb+ "). The resultant object should be checked for validity using
function isValid() .
~RWFile();
Performs any pending I/O operations and closes the file.
Public member functions long CurOffset();
Returns the current position, in bytes from the start of the file, of the file
pointer.
RWBoolean Eof();
Returns TRUE if an end-of-file has been encountered.
RWBoolean Erase();
Erases the contents but does not close the file. Returns TRUE if the operation
was successful.