....
GLuint index1 = glGetUniformBlockIndex(shader.getProgramID(), "test_unif1");
GLuint index2 = glGetUniformBlockIndex(shader.getProgramID(), "test_unif2");
....
glGetActiveUniformBlockiv(shader.getProgramID(), index1, GL_UNIFORM_BLOCK_ACTIVE_UNIFORM_INDICES, (GLint*)&inds1[0]);
glGetActiveUniformsiv(shader.getProgramID(),unifLen,inds1,GL_UNIFORM_OFFSET,offsets1);
glGetActiveUniformBlockiv(shader.getProgramID(), index1,GL_UNIFORM_BLOCK_DATA_SIZE, &size1);
glGetActiveUniformBlockiv(shader.getProgramID(), index2, GL_UNIFORM_BLOCK_ACTIVE_UNIFORM_INDICES, (GLint*)&inds2[0]);    glGetActiveUniformsiv(shader.getProgramID(),unifLen,inds2,GL_UNIFORM_OFFSET,offsets2);
glGetActiveUniformBlockiv(shader.getProgramID(), index2,GL_UNIFORM_BLOCK_DATA_SIZE, &size2);
glGenBuffers( 2, &ubo[0] );
glBindBuffer( GL_UNIFORM_BUFFER, ubo[0] );
glBufferData( GL_UNIFORM_BUFFER, size1, NULL,
                  GL_STATIC_DRAW );
void* buffer = glMapBuffer(GL_UNIFORM_BUFFER, GL_WRITE_ONLY);
....
glUnmapBuffer(GL_UNIFORM_BUFFER);
glBindBuffer( GL_UNIFORM_BUFFER, ubo[1] );
glBufferData( GL_UNIFORM_BUFFER, size2, NULL,
                  GL_STATIC_DRAW );
buffer = glMapBuffer(GL_UNIFORM_BUFFER, GL_WRITE_ONLY);
....
glUnmapBuffer(GL_UNIFORM_BUFFER);
glUniformBlockBinding(shader.getProgramID(), index1, 0);
glUniformBlockBinding(shader.getProgramID(), index2, 1);
glBindBufferBase(GL_UNIFORM_BUFFER, 0, ubo[0]);
glBindBufferBase(GL_UNIFORM_BUFFER, 1, ubo[1]);