----- "Bob Montgomery" <bob.montgomery@xxxxxx> wrote: > I really like to use the x command in crash, as in: > > crash-4.0.9> x/256xg 0xffff8801aa9c8000 > 0xffff8801aa9c8000: 0xffff8800c61541c0 0xffff880145a194c0 > 0xffff8801aa9c8010: 0xffff88016fa481c0 0xffff88016c7980c0 > ... > > > I like it better than the rd command (because of prior familiarity > perhaps?): > crash-4.0.9> rd -x -64 0xffff8801aa9c8000 256 > ffff8801aa9c8000: ffff8800c61541c0 ffff880145a194c0 > ffff8801aa9c8010: ffff88016fa481c0 ffff88016c7980c0 > ... BTW, you don't need the "-x", the "-64", or the "0x" -- given that they are the defaults. So "rd" beats "x" 21 to 25 in keystrokes required... ;-) > > But I *really* like crash's ability to pipe and redirect commands, but > that doesn't work with the x command: > > crash-4.0.9> x/256xg 0xffff8801aa9c8000 | grep ffff880145a194c0 > crash-4.0.9> > > But it works with rd: > > crash-4.0.9> rd -x -64 0xffff8801aa9c8000 256 | grep ffff880145a194c0 > ffff8801aa9c8000: ffff8800c61541c0 ffff880145a194c0 > crash-4.0.9> > > Another fun one: > crash-4.0.9> x/256xg 0xffff8801aa9c8000 | head > Argument to arithmetic operation not a number or boolean. > > > If you redirect the output of x, you get a file containing an error > message: > > crash-4.0.9> x/256xg 0xffff8801aa9c8000 >xold.out > crash-4.0.9> !sh > sh-3.2$ cat xold.out > No symbol "xold" in current context. > sh-3.2$ > > The problem is that the setup of gdb commands in is_gdb_command() with > merge_orig_args set puts the "| thing" or "> thing" back onto the > command it is building to be passed through to gdb. > > I first thought that cmd_gdb() passing a NULL, instead of the fp with > the redirection set up, into gdb_pass_through was part of the problem > also, but that seems to be dealt with later in gdb_interface. > > There might some other reason for the strange behavior of > merge_orig_args that my testing has not found. But otherwise, the > attached patch will allow my favorite x command to be sent through pipes > and redirected to files. Nice. What your patch does is to accurately mimic what happens when you precede your command with "gdb", as in: crash> gdb x/256xg 0xffff8801aa9c8000 > xold.out The syntax above works with crash as it is now, but your patch allows it to work without having to prepend the "gdb". I never noticed that anomoly before, probably because I rarely use gdb commands, and when I do, I usually don't redirect them. Queued for the next release. Thanks, Dave -- Crash-utility mailing list Crash-utility@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/crash-utility
