public override long Seek(long offset, SeekOrigin origin)
{
this.AssertNotDisposed();
if (!this.CanSeek)
{
throw new NotSupportedException("The File Stream does not support seeking");
}
SeekFlags seekFlag = SeekFlags.SEEK_CUR;
switch (origin)
{
case SeekOrigin.Begin:
{
seekFlag = SeekFlags.SEEK_SET;
break;
}
case SeekOrigin.Current:
{
seekFlag = SeekFlags.SEEK_CUR;
break;
}
case SeekOrigin.End:
{
seekFlag = SeekFlags.SEEK_END;
break;
}
default:
{
throw new ArgumentException("origin");
}
}
if (Stdlib.fseek(this.file, offset, seekFlag) != 0)
{
throw new IOException("Unable to seek", UnixMarshal.CreateExceptionForLastError());
}
long num = Stdlib.ftell(this.file);
if (num == (long)-1)
{
throw new IOException("Unable to get current file position", UnixMarshal.CreateExceptionForLastError());
}
GC.KeepAlive(this);
return(num);
}
public override long Seek(long offset, SeekOrigin origin)
{
AssertNotDisposed();
if (!CanSeek)
{
throw new NotSupportedException("The File Stream does not support seeking");
}
Native.SeekFlags sf = Native.SeekFlags.SEEK_CUR;
switch (origin)
{
case SeekOrigin.Begin:
sf = Native.SeekFlags.SEEK_SET;
break;
case SeekOrigin.Current:
sf = Native.SeekFlags.SEEK_CUR;
break;
case SeekOrigin.End:
sf = Native.SeekFlags.SEEK_END;
break;
default:
throw new ArgumentException("origin");
}
int r = Native.Stdlib.fseek(file, offset, sf);
if (r != 0)
{
throw new IOException("Unable to seek",
UnixMarshal.CreateExceptionForLastError());
}
long pos = Native.Stdlib.ftell(file);
if (pos == -1)
{
throw new IOException("Unable to get current file position",
UnixMarshal.CreateExceptionForLastError());
}
GC.KeepAlive(this);
return(pos);
}
private static IntPtr Fopen(string path, string mode)
{
if (path.Length == 0)
{
throw new ArgumentException("path");
}
if (mode == null)
{
throw new ArgumentNullException("mode");
}
IntPtr f = Native.Stdlib.fopen(path, mode);
if (f == IntPtr.Zero)
{
throw new DirectoryNotFoundException("path",
UnixMarshal.CreateExceptionForLastError());
}
return(f);
}
public static void ThrowExceptionForLastError()
{
throw UnixMarshal.CreateExceptionForLastError();
}