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#ifndef POSIX_STREAM_H
#define POSIX_STREAM_H
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <streambuf>
#include <string>
#include <cstddef>
// Customized implementation of Josuttis p673-681.
// It is too brittle to be reusable as is.
class PosixBuf : public std::streambuf {
const int fd_;
char outbuffer_[4096];
static const ptrdiff_t in_back_ = 4;
char inbuffer_[4096 + in_back_];
public:
// see open() parameters for constructor
PosixBuf(const std::string & file_name, int open_flags, int mode = 0);
virtual ~PosixBuf();
int FD() const { return fd_; }
int Lock(short type) const; // type: see fcntl() struct flock l_type
int Truncate(off_t len = 0) const;
private:
int_type FlushBuffer();
virtual int_type overflow(int_type c);
virtual int_type underflow();
virtual int sync();
virtual pos_type seekpos(pos_type, std::ios_base::openmode);
};
#endif
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