X throws out errors when forkpty is called. (C++)

Question

When my program gets to this line:

pid_t nPid = forkpty( &m_nMasterFD, NULL, NULL, NULL );

Outputs this:

X Error: BadIDChoice (invalid resource ID chosen for this connection) 14
  Extension:    148 (RENDER)
  Minor opcode: 17 (RenderCreateGlyphSet)
  Resource id:  0x3600002
<unknown>: Fatal IO error 4 (Interrupted system call) on X server :0.0.

And terminates. As you can see, I'm trying to make a pty to run stuff in, but it's not working.

Also, is there a way forkpty() can be called within a class? ( I tried both ways, but neither worked. )

I'm programming in QT C++ on Ubuntu 9.10.

EDIT: Here's a link to the question with the code that finally worked for me.

Answer 1

forkpty() forks your process. You need to close the filedescriptors first, in particular the connection to the X server in your child process. This means you likely cannot use forkpty , but have to use openpty(), fork(),close filedescriptors in the child process, logintty/()