Patch expect-5.38.0-spawn-43310.patch installation problem of reverse CT

The installation problem of patch expect-5.38.0-spawn-43310.patch-Linux general technology-Linux technology and application information, the following is a detailed reading. Install a spawn patch for your documents. There is a question about the path to be entered during installation.
During installation, the following message is displayed:
[Root @ laserver failed CT-5.43] # patch-Np1-I ../expect-5.38.0-spawn-43310.patch
Can't find file to patch at input line 3
Perhaps you used the wrong-p or -- strip option?
The text leading up to this was:
--------------------------
| --- Tcltk-8.3.1/expect5.31/exp_chan.c.read Fri Nov 16 00:14:15 2001
| ++ Tcltk-8.3.1/expect5.31/exp_chan.c Fri Nov 16 00:14:15 2001
--------------------------
File to patch:

What does this File to patch mean? What I'm wondering is, who does the secondary CT install on the machine itself? However, many documents on the Internet say that you need to patch the patch before installing CT-5.43.