wyregfile.3wy

一个不错

.PP
    [\fBRet\fP] Pointer of the allocated object, or NULL if failed.
          User is responsible to \fBdelete\fP the returned object.
.\"--------------------------------------------
.PP
.BI "virtual WyRet read(void* " "buf" ", size_t " "count" ", size_t& " "n_read" ")"
.PP
    Read at most \fIcount\fP bytes of data from the current r/w position
    into memory pointed by \fIbuf\fP.

    \fIn_read\fP is always written with the bytes read and stored
    into \fIbuf\fP.
.PP
    [\fBRet\fP] Ok              Succeed. Zero byte read means End-of-file.
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal before any data read
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_EFAULT      \fIbuf\fP is inaccessible
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::pread(int,void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet read(WyStr&" " buf" ", size_t " "count" ", size_t& " "n_read" ")"
.PP
    Read at most \fIcount\fP bytes of data from the current r/w position
    and \fBappend\fP to \fIbuf\fP.

    \fIn_read\fP is always written with the bytes read and appended
    to \fIbuf\fP.
.PP
    [\fBRet\fP] Ok              Succeed. Zero byte read means End-of-file.
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal before any data read
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::pread(int,void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(const void* " "buf" ", size_t " "count" ", size_t& " "n_written" ")"
.PP
    Write data indicated by \fIbuf\fP to the system file from the
    current r/w position. The number of written bytes is always
    stored into \fIn_written\fP and added to the current r/w position.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFAULT      \fIbuf\fP is inaccessible
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::pwrite(int,const void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(WyCSeg " "buf" ", size_t& " "n_written" ")"
.PP
    Write data indicated by \fIbuf\fP to the system file from the
    current r/w position. The number of written bytes is always
    stored into \fIn_written\fP and added to the current r/w position.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::pwrite(int,const void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet write(const WyStr& " "buf" ", size_t& " "n_written" ")"
.PP
    Write data indicated by \fIbuf\fP to the system file from the
    current r/w position. The number of written bytes is always
    stored into \fIn_written\fP and added to the current r/w position.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EINVAL      Object attatched device is not suitable
          Wym_EFBIG       Attempt to write beyond the device limit 
          Wym_EAGAIN      Non-blocking I/O (write would block)
          Wym_EINTR       Interrupted by a signal before data written
          Wym_ENOSPC      Device left no space for the operation
          Wym_EIO         Low level I/O error
.PP 
    [\fBRefer\fP] ::pwrite(int,const void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet fsync(void)"
.PP
    Wait untill all the in-core parts of *this associated file has
    written to device
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for writting
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for the operation
          Wym_EROFS       Read-only file system
.PP 
    [\fBRefer\fP] ::fsync(int)
.\"--------------------------------------------
.PP
.BI "virtual WyRet fdatasync(void)"
.PP
    Wait untill the in-core written data has written to device
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for writting
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for the operation
          Wym_EROFS       Read-only file system
.PP 
    [\fBRefer\fP] ::fdatasync(int)
.\"--------------------------------------------
.PP
.BI "off_t pos(void) const"
.PP
    Get the r/w position that the next r/w operation begins with
.PP
    [\fBRet\fP] The position that the next r/w operation begins with
.\"--------------------------------------------
.PP
.BI "virtual void set_pos(off_t " "ofst" ")"
.PP
    Set the next r/w position to begin with \fIofst\fP
    If *this is default, no effect.
.\"--------------------------------------------
.PP
.BI "virtual WyRet seek_end(void)" 
.PP
    Seek the r/w position to one more byte farther than where 
    the farest written byte is. So the next pos() call gets
    the value equivalent to the overall length of the file.
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       \fIregf\fP is not valid for the operation
          Wym_ESPIPE      Illegal seek
.PP 
    [\fBRefer\fP] ::lseek(int,off_t,int)
.\"--------------------------------------------
.PP
.BI "virtual WyRet resize(off_t " "length" ")" 
.PP
    Resize the file to exactly \fIlength\fP bytes.

    Note: r/w position of *this is intact.
.PP
    [\fBRet\fP] Ok              Succeed.
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       Attempt to write beyond the limit
          Wym_EINTR       Interrupted by a signal before data written
          Wym_EINVAL      Device is not suitable for writing
          Wym_EIO         Low level I/O error
          Wym_EROFS       Read-only file system
          Wym_ETXTBSY     Text file busy (see man.)
.PP 
    [\fBRefer\fP] ::ftruncate(int,size_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet _read_till(void* " "buf" ", size_t " "count" ", size_t& " "n_read" ", char " "c" ")"
.PP
    Read at most \fIcount\fP bytes from the file till the read byte
    is equivalent to \fIc\fP(or End-of-file), store the read bytes into
    \fIbuf\fP. 

    Member is for convenience defined on read(void*,size_t,size_t&),

    \fIn_read\fP is always written with the bytes read and stored into \fIbuf\fP.

    Note: Trailing bytes of stored result in \fIbuf\fP may be modified.

    Note: Operation takes place from the current r/w position.
          Failure does not update r/w position

    Note: This member may be inefficient with frequent use.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_EFAULT      \fIbuf\fP is inaccessible
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::pread(int,void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "virtual WyRet _read_till(WyStr& " "buf" ",size_t " "count" ", size_t& " "n_read" ", char " "c" ")"
.PP
    Read at most \fIcount\fP bytes from the file till the read byte
    is equivalent to \fIc\fP(or End-of-file), \fBappend\fP the read bytes
    into \fIbuf\fP. 

    Member is for convenience defined on read(void*,size_t,size_t&),

    \fIn_read\fP is always written with the bytes read and appended to \fIbuf\fP.

    Note: Reallocation of \fIbuf\fP may occur.

    Note: Operation takes place from the current r/w position.
          Failure does not update r/w position

    Note: This member may be inefficient with frequent use.
.PP
    [\fBRet\fP] Ok              Succeed
          Wym_EBADF       Object is not valid for the operation
          Wym_EFBIG       \fIcount\fP exceeds the maximum
          Wym_EINTR       Interrupted by a signal
          Wym_EAGAIN      Non-blocking I/O (no data read)
          Wym_EIO         Low level I/O error
          Wym_EINVAL      Device is not suitable for reading
          Wym_ENOMEM      Not enough memory for \fIcount\fP
.PP 
    [\fBRefer\fP] ::pread(int,void*,size_t,off_t)
.\"--------------------------------------------
.PP
.BI "static WyRet create(WyRegFile& " "regf" ",const char* " "pathname" ",int " "f" ", mode_t " "m" ")" 
.PP
.BI "static WyRet create(WyRegFile& " "regf" ",const WyStr& " "pathname" ",int " "f" ", mode_t " "m" ")" 
.PP
    Create a system regular file \fIpathname\fP with mode \fIm\fP and 
    reset \fIregf\fP to the state as constructed by WyRegFile(\fIpathname\fP,\fIf\fP)

      \fIf\fP= flags for ::open
      \fIm\fP= specifies permissions, the same as ::open(...)
.PP
    [\fBRet\fP] Ok              Succeed. r/w position is set to zero
          Wym_EACCES      Search permission is denied
          Wym_ENAMETOOLONG \fIpathname\fP too long
          Wym_ENOENT      \fIpathname\fP does not exist
          Wym_ENOTDIR     Entry in \fIpathname\fP is not a directory
          Wym_EMFILE      Too many open fd
          Wym_ENFILE      File table overflow
          Wym_ENOMEM      Not enough memory
          Wym_EEXIST      Pathname already exists
          Wym_EINTR       Interrupted by a signal
          Wym_ENOSPC      Device left no space for the operation
          Wym_ENXIO       No such device (device not ready)
          Wym_EROFS       Read-only file system
          Wym_ENODEV      No such device
          Wym_ELOOP       Too many symbolic links encountered
          ...             reply converted from the errno from ::open
.PP 
    [\fBRefer\fP] ::open(const char*,int,mode_t)
.\"--------------------------------------------
.PP
.BI "static WyRet create_tmpfile(WyRegFile& " "regf" ", WyStr& " "name_temp" ")" 
.PP
    Create a system regular file of the unique filename formed by
    appending system generated (six)characters to the argument
    \fIname_temp\fP, and reset \fIregf\fP to the state as constructed by
    WyRegFile(\fIname_temp\fP,\fIf\fP), where \fIf\fP and the file mode are
    system dependent.
.PP
    [\fBRet\fP] Ok              Succeed. r/w position is set to zero
          Wym_ENAMETOOLONG \fIname_temp\fP too long
          Wym_ENOMEM      Not enough memory
          Wym_EEXIST      Failed to create an unique filename
.PP 
    [\fBRefer\fP] ::mkstemp(char*)
.\"--------------------------------------------
.SH "SEE ALSO"
.BR wyret
.BR wyfilehandle
.BR wyfilestat
.BR wychrfile
.BR wysockfile
.BR wymutex
.BR wytimespec
.SH NOTE
Except added by this library, replys are converted from the errno 
an underlying C library function returned. Report of such replys
are brief from Linux Programmer's Manual. See the associated man page
for details.

Project is in development, http://sourceforge.net/projects/libwx