Where does HOST_OPERATING_SYSTEM in uname.c comes from?

Question

While reading uname.c (in order to recreate it) I found a variable called HOST_OPERATING_SYSTEM (line 371). It's never mentioned in the same file (as Strg+f told me) and not in the dependencies of uname.c, as far as I could see.

Where is the variable initialized and how to access it?

I think this might get defined by the build system of the project (with some autoconf/automake macros?) — Julien Thierry, May 10 '20 at 11:43
Check the Makefile, to see if some option to the compiler like `-DHOST_OPERATING_SYSTEM=something`. — Luis Colorado, May 12 '20 at 22:46

score 3 · Accepted Answer · answered May 10 '20 at 13:05

3

HOST_OPERATING_SYSTEM is defined at build time using autoconf modules defined in gnulib.

answered May 10 '20 at 13:05

larsks

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where is it stored? How does uname access it later on? – Asqiir May 10 '20 at 15:28
It's a C `#define`. It ends up hardcoded into the `uname` binary. – larsks May 10 '20 at 15:39

Where does HOST_OPERATING_SYSTEM in uname.c comes from?

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