I am using GrassGIS to analyze watershed. I created a stream vector extracted from raster elevation data, how to extract the stream vector file so I can open it using QGIS?
You may export to Shapefile with
Example from the doc:
v.out.ogr input=lines type=line output=lines.shp
QGIS has the ability to connect to GRASS. Follow the links below to integrate the GRASS plugin with QGIS to add GRASS vector data to QGIS and export it into a shapefile or any other format.