problem about using tmux while debugging

[chujDK]

Hello, I have been using tmux and gdb as the debugger to debug for a while. However i got error while using it now.

I wrote my exp with following method

• fisrtly, set the terminal
  context.terminal = ["tmux", 'splitw', '-h']
• secondly use gdb.attach to attach the program

sh = process("...")
...
gdb.attach(proc.pidof(sh)[0])

it used work, but now i get error like

[DEBUG] Launching a new terminal: ['/usr/bin/tmux', 'splitw', '-h', '/usr/bin/gdb -q  "/home/chuj/com/TCTF/LB/listbook" 19995']              
Traceback (most recent call last):                                                                                                           
  File "listbook_exp.py", line 37, in <module>                                                                                               
    gdb.attach(proc.pidof(sh)[0])                                                                                                            
  File "/home/chuj/.local/lib/python2.7/site-packages/pwnlib/context/__init__.py", line 1543, in setter                                      
    return function(*a, **kw)                                                                                                                
  File "/home/chuj/.local/lib/python2.7/site-packages/pwnlib/gdb.py", line 1051, in attach                                                   
    gdb_pid = misc.run_in_new_terminal(cmd, preexec_fn = preexec_fn)                                                                         
  File "/home/chuj/.local/lib/python2.7/site-packages/pwnlib/util/misc.py", line 297, in run_in_new_terminal                                 
    pid = int(out)                                                                                                                           
ValueError: invalid literal for int() with base 10: '' 

I found the problem is caused by int() function, so i changed site-packages/pwnlib/util/misc.py to that

     if terminal == 'tmux':                                                                                                                                                                                                                                                            
         out, _ = p.communicate()                                                                                                                                                                                                                                                               
         # pid = int(out)                                                                                                                                                                                                                                                                         
         pid = out       

and now it can work. Could you tell me what cause this problem? Is it a bug or my exp's fault?

[Arusekk]

Fixed by #1902. Either update (can't remember which version, but dev certainly has it), or use a workaround mentioned here: #1874 (comment)