trying to figure out the logic...

[D. Stimits]

This isn't a bug, but I'm perplexed in trying to figure out something in 
how ncurses is implemented (this is ncurses 5.3, redhat 7.3). I'm 
looking at the type SCREEN, and see it typedef'd to struct screen. I'm 
looking because I am trying to figure out how a SCREEN* can provide a 
WINDOW*. My discovery is that, recursively within /usr/include/, that 
struct screen is never prototyped. I even ran gcc with a -E to 
preprocess it and stop, the output never gave the prototype of struct 
screen, only the alias with typedef struct screen SCREEN. Being that it 
always uses only a pointer to the SCREEN, perhaps it only needs to know 
the size of a pointer, and thus the actual knowledge of struct screen is 
not needed in the client application. But where in the heck is struct 
screen prototyped? And how does one use the SCREEN* from newterm() to 
get a WINDOW* that many of the other calls require? I ran gdb on this 
and told it to give me the value of the struct, and found it is rather 
large and complex, then did a recursive grep on the members from gdb, 
and still could not find the file with those members...is the actual 
struct only touched within the libraries, and all clients use only 
pointers, thus removing the need to declare the actual struct screen 
contents within client apps?

D. Stimits, stimits AT attbi DOT com