Bug 31420

texlive-base-2008.0-alt0.15
texlive-recommended-2008.0-alt0.15
texlive-extra-2008.0-alt0.16

https://www.ctan.org/tex-archive/macros/latex/contrib/iftex says that iftex.sty is included in texlive, but it is missing in ALT's tex* packages.

It's used by some authors in some other packages, for example, in the one from https://bugzilla.altlinux.org/show_bug.cgi?id=31414 (which requires iftex).

It's present in Ubuntu's packages: http://packages.ubuntu.com/search?lang=fr&suite=quantal&arch=i386&mode=filename&searchon=contents&keywords=iftex (just what some first Google results showed me).

Perhaps, the reason is: texlive in ALTLinux is quite old.