GDB examine data display format from 8 bytes in a row to 4 bytes

Question

This is the display of my gdb

(gdb) x/20bx 0xbffff2c0
0xbffff2c0: 0xd4    0xf2    0xff    0xbf    0x16    0x8f    0x04    0x08
0xbffff2c8: 0x05    0x00    0x00    0x00    0x00    0x00    0x0c    0x42
0xbffff2d0: 0x6b    0x00    0x00    0x00

Is is possible to change it to 4 bytes in a row?

Answer 1

gdb (at least in the 7.1 and 7.6 source I looked at) hard-wires the maximum number of elements per line that x will print, based on the format.

maxelts = 8;
if (size == 'w')
  maxelts = 4;
if (size == 'g')
  maxelts = 2;
if (format == 's' || format == 'i')
  maxelts = 1;

A workaround to get what you want is to type x/4bx 0xbffff2c0 to print 4 elements and then type just enter to print each successive set of 4 elements.