readshapefile fails on certain filenames

还没有人认领这个 Issue。

Hi,

(Tested with basemap 1.0.6)

This works:

`m.readshapefile('foo.shp', 'my_shape')`

while this fails:

`m.readshapefile('bar_0.1.shp', 'my_shape')`

```
raise IOError('error reading shapefile %s.shp' % shapefile)
fields = shf.fields
coords = []; attributes = []

IOError: error reading shapefile bar_0.1.shp
```

Note that foo.shp and bar_0.1.shp are exactly the same file except for the filename. So it seems that the additional `.` causes the problem. Minimal example to reproduce behavior:

Rename `huralll020.{shp,dfb,shx}` to `huralll020_0.1.{shp,dbf,shx}` and change filename in `examples/hurrtracks.py` accordingly. Run hurrtracks.py.

Of course the obvious workaround is not to use `.` in filenames. But this is somewhat impracticable as I have a large number or files and would like keeping the filenames consistent accross filetypes (netCDF, shapfiles, pngs, etc).

Is there an easy fix?

Thanks very much,

Andy

从 readshapefile 入口点以及 examples/hurrtracks.py 中的复现开始。按照描述重命名 huralll020 的 shapefile 组件，运行 hurrtracks.py，并跟踪带点的文件名失败的原因。当同一个 shapefile 可以使用类似 huralll020_0.1 的文件名读取，且现有示例仍然正常工作时，即表示完成。

由索引模型根据 Issue 内容生成。