The block size determines how many bytes radare2 commands will process when not given an explicit size argument. You can temporarily change the block size by specifying a numeric argument to the print commands. For example
[0xB7F9D810]> b? | Usage: b[f] [arg] | Get/Set block size | b 33 set block size to 33 | b eip+4 numeric argument can be an expression | b display current block size | b+3 increase blocksize by 3 | b-16 decrease blocksize by 16 | b* display current block size in r2 command | bf foo set block size to flag size | bj display block size information in JSON | bm 1M set max block size
b command is used to change the block size:
[0x00000000]> b 0x100 ; block size = 0x100 [0x00000000]> b+16 ; ... = 0x110 [0x00000000]> b-32 ; ... = 0xf0
bf command is used to change the block size to value specified by a flag. For example, in symbols, the block size of the flag represents the size of the function.
[0x00000000]> bf sym.main ; block size = sizeof(sym.main) [0x00000000]> pd @ sym.main ; disassemble sym.main ...
You can combine two operations in a single one (
[0x00000000]> pdf @ sym.main