ref: 8b3f4d8a37dce7944e0fb5ca716ad6eadbe7d7d8 dir: /sys/src/cmd/plot/libplot/erase.c/
#include "mplot.h" void erase(void){ m_swapbuf(); m_clrwin(clipminx, clipminy, clipmaxx, clipmaxy, e1->backgr); }