filebuf.cpp

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#include <fstream>    // for filebuf, ifstream, istream
#include <iostream>   // for cout, endl
#include <cstdio>     // for tmpnam(), remove()
 
#include <examples.h>
 
int main ()
{
#ifndef _RWSTD_NO_EXT_FILEBUF
 
    // use an extension of this implementation: NULL file name argument
    // creates a temporary file; closing the file stream object or its
    // associated filebuf removes the temporary file
    const char* const fname = 0;
    
#else   // if defined (_RWSTD_NO_EXT_FILEBUF)
 
    char fnamebuf [L_tmpnam];
 
    // create a temporary filename
    const char* const fname = std::tmpnam (fnamebuf);
 
    if (!fname)
        return 1;
 
#endif   // _RWSTD_NO_EXT_FILEBUF
 
    // create a filebuf object for reading and writing of a temporary file
    std::filebuf outbuf;
 
    outbuf.open (fname, std::ios::in | std::ios::out | std::ios::trunc);
 
    // set the internal character buffer size
    // buffer will be allocated internally and deallocated in object dtor
    outbuf.pubsetbuf (0, 256);
 
    // associate the filebuf object with an iostream object
    std::iostream out (&outbuf);
 
    // open this source code file and output it to the temporary file
    out << std::ifstream (__FILE__).rdbuf ();
  
    // seek to the beginning of the stream
    out.seekp (0);
 
    // output the contents of the `out' object to standard output
    std::cout << out.rdbuf ();  
 
    // close the filebuf object before removing the underlying file
    outbuf.close ();
  
    if (fname) {
        // remove the temporary file if it has a name
        // otherwise, if fname is NULL, the temporary file will
        // have already been automatically removed by the call
        // to close() above
        std::remove (fname);
    }
 
    return 0;
}