Maybe it's very stupid question but I can't find out the answer.
I've neverr tried to write a spec file for rpm package until today. I found an example of spec and I see a lot of %{__install} thinks in the %install section. As far as I understand by the syntax it's a king of makros. But there is no defenition for it in the spec files. In my example it looks like this:
%install
%{__install} -pD -m 644 $RPM_BUILD_DIR/my-project-%{version}/deploy/my-project.service $RPM_BUILD_ROOT/usr/lib/systemd/system/my_project-emperor.service
I also seen a lot of examples with this macros in other spec-s I've found. Like this or that. They have the same syntax:
%{__install} -s %{name} %{buildroot}%{_sbindir}/
%{__install} -c -m 644 examples/acl-content-sw.cfg %{buildroot}%{_sysconfdir}/%{name}/%{name}-acl-content-sw.cfg.example
%{__install} -c -m 644 examples/auth.cfg %{buildroot}%{_sysconfdir}/%{name}/%{name}-auth.cfg.example
But what %{__install} actually is? Some kind of built-in macros for rpm builder? It's hard to google it or find it in the official docs, but it looks like it's a some kind of common thing.
Unfortunately there is no magical answer. Rpm macros can be redefined differently on different OS and can even be redefined afterwards by other packages.
Default definitions can be found in /usr/lib/rpm/macros, but other packages can install more macros in /usr/lib/rpm/macros.d/.
in my /usr/lib/rpm/macros if found this definition:
%__install /usr/bin/install
so in this case the macro %__install doesn't really add anything.
But I find the %make_install macro rather handy; which is defined as:
%make_install %{__make} install DESTDIR=%{?buildroot} INSTALL="%{__install} -p"
so instead of putting
make install DESTDIR=%{?buildroot}
I can just put
%make_install
in my spec file... (and while explaining this; I just got to know the -p option of install :) )