Section 5.12.2 of Linux From Scratch 7.4 lists the installed library of expect as libexpect-5.45.a but after building and installing expect5.45 my lfs/tools/lib/expect5.45 directory contains libexpect5.45.so

I assume this should be reported as a bug to be corrected in the next edition but it's not clear where to report it.

In the BLFS book, just for comparison, the expect page lists the shared library being installed just as you discovered in your LFS tools dir (not a static library as the LFS book says). The configure command in the BLFS book includes --enable-shared which would install the .so library. Even though the LFS expect page does not include the --enable-share configure option, the configure --help information for expect-5.45 (which I just looked at) states that --enable-shared is the default. So I would expect the installed library to be the .so as you found. This exact situation seems to go back to at least LFS v6.8 which used the same version of expect. To me, this is probably a simple typo in the LFS book. If you like, you can report it either by creating a new ticket at the LFS wiki or by posting it in one of the LFS mailing lists (say, lfs-dev or lfs-support). I've reported stuff like that both ways. Doesn't really matter much since the same guys all read all of that stuff. They seem to appreciate it. Go to http://www.linuxfromscratch.org/ and follow links to the wiki or the mailing lists.

Thanks stoat. I opened a ticket on the wiki.

I agree that it's a typo. I didn't mean to imply that there was anything wrong with the library itself. When I wrote "bug" I was referring to the documentation error.

There's a few errors still in the book that pop up from time to time or are noticed.

Somebody has already fixed this matter in the development version of the book (and I did check there the other day, too). So you made a little contribution to the book. Now, if you end up really liking B/LFS (like I do), they mostly appreciate this proof-reading kind of help when the release candidates come out. Those are for people to test the steps and read the text and so on looking for things that need to be fixed for the final release. The release schedule lately has been March and September, so a release candidate probably will be available in a mere couple of weeks. Sometimes I build the release candidate, and sometimes not. Sometimes the release candidate becomes the final version. Anyway, I try to help these people out when I can. I also donate money to Beekmans for every new release. BLFS is the only Linux distro (and very nearly the only OS) that I use. I value it and the project.