Linux From Scratch (w/Pacman) - Version r12.3-6-wip

Chapter 8. Installing Basic System Software

8.19. Expect-5.45.4

The Expect package contains tools for automating, via scripted dialogues, interactive applications such as telnet, ftp, passwd, fsck, rlogin, and tip. Expect is also useful for testing these same applications as well as easing all sorts of tasks that are prohibitively difficult with anything else. The DejaGnu framework is written in Expect.

Approximate build time: 0.2 SBU
Required disk space: 3.9 MB

8.19.1. Installation of Expect

Expect needs PTYs to work. Verify that the PTYs are working properly inside the chroot environment by performing a simple test: 

python3 -c 'from pty import spawn; spawn(["echo", "ok"])'

This command should output ok. If, instead, the output includes OSError: out of pty devices, then the environment is not set up for proper PTY operation. You need to exit from the chroot environment, read Section 7.3, “Preparing Virtual Kernel File Systems” again, and ensure the devpts file system (and other virtual kernel file systems) mounted correctly. Then reenter the chroot environment following Section 7.4, “Entering the Chroot Environment”. This issue needs to be resolved before continuing, or the test suites requiring Expect (for example the test suites of Bash, Binutils, GCC, GDBM, and of course Expect itself) will fail catastrophically, and other subtle breakages may also happen.

Create the PKGBUILD for the Expect package with the following commands: 

mkdir /sources/expect
cd /sources/expect
cat > PKGBUILD << "REALEOF"
# Maintainer: Linux From Scratch <lfs-dev@lists.linuxfromscratch.org>

pkgname="expect"
pkgver="5.45.4"
pkgrel="2"
pkgdesc="The Expect package contains tools for automating, via scripted dialogues, interactive applications."
arch=('x86'
      'x86_64')
url="https://core.tcl.tk/expect/"
license=('PD')
groups=('core')
depends=('glibc'
         'tcl')
optdepends=('tk')
makedepends=('bash'
             'binutils'
             'coreutils'
             'diffutils'
             'gcc'
             'grep'
             'make'
             'patch'
             'sed')
source=('https://prdownloads.sourceforge.net/expect/expect5.45.4.tar.gz'
        'https://www.linuxfromscratch.org/patches/lfs/development/expect-5.45.4-gcc14-1.patch)
md5sums=('00fce8de158422f5ccd2666512329bd2'
         '0b8b5ac411d011263ad40b0664c669f0)

prepare(){
  cd "${pkgname}${pkgver}"
  # Allow the package with gcc-14.1 or later
  patch -Np1 -i "../${pkgname}-${pkgver}-gcc14-1.patch"
}

build() {
  # Remove -Werror from CFLAGS
  CFLAGS=${CFLAGS/-Werror=format-security/}

  cd "${pkgname}${pkgver}"
  ./configure --prefix=/usr           \
              --with-tcl=/usr/lib     \
              --enable-shared         \
              --disable-rpath         \
              --disable-werror        \
              --mandir=/usr/share/man \
              --with-tclinclude=/usr/include
make
}

check() {
  cd "${pkgname}${pkgver}"
  make test
}

package() {
  cd "${pkgname}${pkgver}"
  make DESTDIR="${pkgdir}" install
  ln -svf "${pkgname}${pkgver}/lib${pkgname}${pkgver}.so" "${pkgdir}/usr/lib"
}
REALEOF

The meaning of the configure options:

--with-tcl=/usr/lib

This parameter is needed to tell configure where the tclConfig.sh script is located.

--with-tclinclude=/usr/include

This explicitly tells Expect where to find Expect's internal headers.

Prepare the build directory for the pacman user and build the package: 

chown -R root:pacman .
chmod 2775 .
chmod 664 PKGBUILD
su pacman -c 'makepkg -L --nodeps'

Add the newly created package to the central package repository: 

cp expect-5.45.4-2-$(uname -m).pkg.tar.xz \
   /srv/pacman/repos/LFS/
repo-add /srv/pacman/repos/LFS/LFS.db.tar.xz \
         /srv/pacman/repos/LFS/expect-5.45.4-2-$(uname -m).pkg.tar.xz

Update the local cache and install the Expect package: 

pacman -Syu
pacman -S expect --overwrite \* -dd --noconfirm

Finally, copy the source files into the source repository and clean up the build directory: 

mkdir /srv/pacman/source/LFS/expect
cp PKGBUILD /srv/pacman/source/LFS/expect
cd /sources
rm -rf expect

8.19.2. Contents of Expect

Installed program: expect
Installed library: libexpect5.45.4.so

Short Descriptions

expect

Communicates with other interactive programs according to a script

libexpect-5.45.4.so

Contains functions that allow Expect to be used as a Expect extension or to be used directly from C or C++ (without Expect)