don't call setbuf, use optimal size.

[unix-history] / usr / src / old / lib2648 / emptyrow.c

/*      emptyrow.c      4.1     83/03/09        */
/*
* emptyrow: returns true if row r of m is all zeros.
*
* Note that we assume the garbage at the end of the
* row is all zeros.
*/

#include "bit.h"

emptyrow(m, rows, cols, r)
bitmat m;
int rows, cols, r;
{
       char *top, *bot;

       bot = &m[r*((cols+7)>>3)];
       top = bot + ((cols-1) >> 3);
       while (bot <= top)
               if (*bot++)
                       return(0);
       return (1);
}