Linux From Scratch - Version 6.7

Chapter 5. Constructing a Temporary System

5.12. Expect-5.44.1.15

The Expect package contains a program for carrying out scripted dialogues with other interactive programs.

Approximate build time: 0.1 SBU
Required disk space: 4.1 MB

5.12.1. Installation of Expect

First, apply a patch to remove the dependency on Tk, that may be present on the host but will not be available once we enter the chroot environment: 

patch -Np1 -i ../expect-5.44.1.15-no_tk-1.patch

Next, force Expect's configure script to use /bin/stty instead of a /usr/local/bin/stty it may find on the host system. This will ensure that our test suite tools remain sane for the final builds of our toolchain: 

cp -v configure{,.orig}
sed 's:/usr/local/bin:/bin:' configure.orig > configure

Now prepare Expect for compilation: 

./configure --prefix=/tools --with-tcl=/tools/lib \
  --with-tclinclude=/tools/include --with-tk=no

The meaning of the configure options:

--with-tcl=/tools/lib

This ensures that the configure script finds the Tcl installation in the temporary tools location instead of possibly locating an existing one on the host system.

--with-tclinclude=/tools/include

This explicitly tells Expect where to find Tcl's internal headers. Using this option avoids conditions where configure fails because it cannot automatically discover the location of Tcl's headers.

--with-tk=no

This tells the configure script not to search for Tk (the Tcl GUI component) or the X Window System libraries, both of which may reside on the host system but will not exist in the temporary environment.

Build the package: 

make

Compilation is now complete. As discussed earlier, running the test suite is not mandatory for the temporary tools here in this chapter. To run the Expect test suite anyway, issue the following command: 

make test

Note that the Expect test suite is known to experience failures under certain host conditions that are not within our control. Therefore, test suite failures here are not surprising and are not considered critical.

Install the package: 

make SCRIPTS="" install

The meaning of the make parameter:

SCRIPTS=""

This prevents installation of the supplementary Expect scripts, which are not needed.

5.12.2. Contents of Expect

Installed program: expect
Installed library: libexpect-5.44.a

Short Descriptions

expect

Communicates with other interactive programs according to a script

libexpect-5.44.a

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