8.5.1. Installation of Glibc
        
        
          First, fix a security problem identified upstream:
        
        sed -e '/NOTIFY_REMOVED)/s/)/ \&\& data.attr != NULL)/' \
    -i sysdeps/unix/sysv/linux/mq_notify.c
        
          Some of the Glibc programs use the non-FHS compliant /var/db directory to store their runtime data.
          Apply the following patch to make such programs store their runtime
          data in the FHS-compliant locations:
        
        patch -Np1 -i ../glibc-2.34-fhs-1.patch
        
          The Glibc documentation recommends building Glibc in a dedicated
          build directory:
        
        mkdir -v build
cd       build
        
          Ensure that the ldconfig and sln utilites are installed into
          /usr/sbin:
        
        echo "rootsbindir=/usr/sbin" > configparms
        
          Prepare Glibc for compilation:
        
        ../configure --prefix=/usr                            \
             --disable-werror                         \
             --enable-kernel=3.2                      \
             --enable-stack-protector=strong          \
             --with-headers=/usr/include              \
             libc_cv_slibdir=/usr/lib
        
          
            The meaning of the configure options:
          
          
            - 
              --disable-werror
- 
              
                This option disables the -Werror option passed to GCC. This
                is necessary for running the test suite.
               
- 
              --enable-kernel=3.2
- 
              
                This option tells the build system that this glibc may be
                used with kernels as old as 3.2. This means generating
                workarounds in case a system call introduced in a later
                version cannot be used.
               
- 
              --enable-stack-protector=strong
- 
              
                This option increases system security by adding extra code to
                check for buffer overflows, such as stack smashing attacks.
               
- 
              --with-headers=/usr/include
- 
              
                This option tells the build system where to find the kernel
                API headers.
               
- 
              libc_cv_slibdir=/usr/lib
- 
              
                This variable sets the correct library for all systems. We do
                not want lib64 to be used.
               
 
        
          Compile the package:
        
        make
        
          ![[Important]](../images/important.png) 
          
            Important
          
          
            In this section, the test suite for Glibc is considered critical.
            Do not skip it under any circumstance.
          
         
        
          Generally a few tests do not pass. The test failures listed below
          are usually safe to ignore.
        
        make check
        
          You may see some test failures. The Glibc test suite is somewhat
          dependent on the host system. A few failures out of over 4200 tests
          can generally be ignored. This is a list of the most common issues
          seen for recent versions of LFS:
        
        
        
          Though it is a harmless message, the install stage of Glibc will
          complain about the absence of /etc/ld.so.conf. Prevent this warning with:
        
        touch /etc/ld.so.conf
        
          Fix the generated Makefile to skip an unneeded sanity check that
          fails in the LFS partial environment:
        
        sed '/test-installation/s@$(PERL)@echo not running@' -i ../Makefile
        
          Install the package:
        
        make install
        
          Fix hardcoded path to the executable loader in ldd script:
        
        sed '/RTLDLIST=/s@/usr@@g' -i /usr/bin/ldd
        
          Install the configuration file and runtime directory for
          nscd:
        
        cp -v ../nscd/nscd.conf /etc/nscd.conf
mkdir -pv /var/cache/nscd
        
          Install the systemd support files for nscd:
        
        install -v -Dm644 ../nscd/nscd.tmpfiles /usr/lib/tmpfiles.d/nscd.conf
install -v -Dm644 ../nscd/nscd.service /usr/lib/systemd/system/nscd.service
        
          Next, install the locales that can make the system respond in a
          different language. None of the locales are required, but if some
          of them are missing, the test suites of future packages would skip
          important testcases.
        
        
          Individual locales can be installed using the localedef program. E.g., the
          first localedef
          command below combines the /usr/share/i18n/locales/cs_CZ charset-independent
          locale definition with the /usr/share/i18n/charmaps/UTF-8.gz charmap
          definition and appends the result to the /usr/lib/locale/locale-archive file. The
          following instructions will install the minimum set of locales
          necessary for the optimal coverage of tests:
        
        mkdir -pv /usr/lib/locale
localedef -i POSIX -f UTF-8 C.UTF-8 2> /dev/null || true
localedef -i cs_CZ -f UTF-8 cs_CZ.UTF-8
localedef -i de_DE -f ISO-8859-1 de_DE
localedef -i de_DE@euro -f ISO-8859-15 de_DE@euro
localedef -i de_DE -f UTF-8 de_DE.UTF-8
localedef -i el_GR -f ISO-8859-7 el_GR
localedef -i en_GB -f ISO-8859-1 en_GB
localedef -i en_GB -f UTF-8 en_GB.UTF-8
localedef -i en_HK -f ISO-8859-1 en_HK
localedef -i en_PH -f ISO-8859-1 en_PH
localedef -i en_US -f ISO-8859-1 en_US
localedef -i en_US -f UTF-8 en_US.UTF-8
localedef -i es_ES -f ISO-8859-15 es_ES@euro
localedef -i es_MX -f ISO-8859-1 es_MX
localedef -i fa_IR -f UTF-8 fa_IR
localedef -i fr_FR -f ISO-8859-1 fr_FR
localedef -i fr_FR@euro -f ISO-8859-15 fr_FR@euro
localedef -i fr_FR -f UTF-8 fr_FR.UTF-8
localedef -i is_IS -f ISO-8859-1 is_IS
localedef -i is_IS -f UTF-8 is_IS.UTF-8
localedef -i it_IT -f ISO-8859-1 it_IT
localedef -i it_IT -f ISO-8859-15 it_IT@euro
localedef -i it_IT -f UTF-8 it_IT.UTF-8
localedef -i ja_JP -f EUC-JP ja_JP
localedef -i ja_JP -f SHIFT_JIS ja_JP.SIJS 2> /dev/null || true
localedef -i ja_JP -f UTF-8 ja_JP.UTF-8
localedef -i nl_NL@euro -f ISO-8859-15 nl_NL@euro
localedef -i ru_RU -f KOI8-R ru_RU.KOI8-R
localedef -i ru_RU -f UTF-8 ru_RU.UTF-8
localedef -i se_NO -f UTF-8 se_NO.UTF-8
localedef -i ta_IN -f UTF-8 ta_IN.UTF-8
localedef -i tr_TR -f UTF-8 tr_TR.UTF-8
localedef -i zh_CN -f GB18030 zh_CN.GB18030
localedef -i zh_HK -f BIG5-HKSCS zh_HK.BIG5-HKSCS
localedef -i zh_TW -f UTF-8 zh_TW.UTF-8
        
          In addition, install the locale for your own country, language and
          character set.
        
        
          Alternatively, install all locales listed in the glibc-2.34/localedata/SUPPORTED file (it includes
          every locale listed above and many more) at once with the following
          time-consuming command:
        
        make localedata/install-locales
        
          Then use the localedef command to create and
          install locales not listed in the glibc-2.34/localedata/SUPPORTED file when you
          need them. For instance, the following two locales are needed for
          some tests later in this chapter:
        
        localedef -i POSIX -f UTF-8 C.UTF-8 2> /dev/null || true
localedef -i ja_JP -f SHIFT_JIS ja_JP.SIJS 2> /dev/null || true
        
          ![[Note]](../images/note.png) 
          
            Note
          
          
            Glibc now uses libidn2 when resolving internationalized domain
            names. This is a run time dependency. If this capability is
            needed, the instructions for installing libidn2 are in the
            
            BLFS libidn2 page.
          
         
       
      
        
          8.5.2. Configuring Glibc
        
        
          
            8.5.2.1. Adding nsswitch.conf
          
          
            The /etc/nsswitch.conf file needs
            to be created because the Glibc defaults do not work well in a
            networked environment.
          
          
            Create a new file /etc/nsswitch.conf by running the following:
          
          cat > /etc/nsswitch.conf << "EOF"
# Begin /etc/nsswitch.conf
passwd: files
group: files
shadow: files
hosts: files dns
networks: files
protocols: files
services: files
ethers: files
rpc: files
# End /etc/nsswitch.conf
EOF
         
        
          
            8.5.2.2. Adding time zone data
          
          
            Install and set up the time zone data with the following:
          
          tar -xf ../../tzdata2021a.tar.gz
ZONEINFO=/usr/share/zoneinfo
mkdir -pv $ZONEINFO/{posix,right}
for tz in etcetera southamerica northamerica europe africa antarctica  \
          asia australasia backward; do
    zic -L /dev/null   -d $ZONEINFO       ${tz}
    zic -L /dev/null   -d $ZONEINFO/posix ${tz}
    zic -L leapseconds -d $ZONEINFO/right ${tz}
done
cp -v zone.tab zone1970.tab iso3166.tab $ZONEINFO
zic -d $ZONEINFO -p America/New_York
unset ZONEINFO
          
            
              The meaning of the zic commands:
            
            
              - 
                zic -L
                /dev/null ...
- 
                
                  This creates posix time zones without any leap seconds. It
                  is conventional to put these in both zoneinfoandzoneinfo/posix. It is necessary to put
                  the POSIX time zones inzoneinfo, otherwise various test-suites
                  will report errors. On an embedded system, where space is
                  tight and you do not intend to ever update the time zones,
                  you could save 1.9 MB by not using theposixdirectory, but some applications or
                  test-suites might produce some failures.
 
- 
                zic -L
                leapseconds ...
- 
                
                  This creates right time zones, including leap seconds. On
                  an embedded system, where space is tight and you do not
                  intend to ever update the time zones, or care about the
                  correct time, you could save 1.9MB by omitting the
                  rightdirectory.
 
- 
                zic ... -p
                ...
- 
                
                  This creates the posixrulesfile. We use New York because POSIX requires the daylight
                  savings time rules to be in accordance with US rules.
 
 
          
            One way to determine the local time zone is to run the following
            script:
          
          tzselect
          
            After answering a few questions about the location, the script
            will output the name of the time zone (e.g., America/Edmonton). There are also some
            other possible time zones listed in /usr/share/zoneinfo such as Canada/Eastern or EST5EDT that are not identified by the
            script but can be used.
          
          
            Then create the /etc/localtime file
            by running:
          
          ln -sfv /usr/share/zoneinfo/<xxx> /etc/localtime
          
            Replace <xxx>
            with the name of the time zone selected (e.g., Canada/Eastern).
          
         
        
          
            8.5.2.3. Configuring the
            Dynamic Loader
          
          
            By default, the dynamic loader (/lib/ld-linux.so.2) searches through
            /lib and /usr/lib for dynamic libraries that are needed
            by programs as they are run. However, if there are libraries in
            directories other than /lib and
            /usr/lib, these need to be added to
            the /etc/ld.so.conf file in order
            for the dynamic loader to find them. Two directories that are
            commonly known to contain additional libraries are /usr/local/lib and /opt/lib, so add those directories to the
            dynamic loader's search path.
          
          
            Create a new file /etc/ld.so.conf
            by running the following:
          
          cat > /etc/ld.so.conf << "EOF"
# Begin /etc/ld.so.conf
/usr/local/lib
/opt/lib
EOF
          
            If desired, the dynamic loader can also search a directory and
            include the contents of files found there. Generally the files in
            this include directory are one line specifying the desired
            library path. To add this capability run the following commands:
          
          cat >> /etc/ld.so.conf << "EOF"
# Add an include directory
include /etc/ld.so.conf.d/*.conf
EOF
mkdir -pv /etc/ld.so.conf.d