chapter06/glibc.xml

   1 <?xml version="1.0" encoding="ISO-8859-1"?>
   2 <!DOCTYPE sect1 PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
   3   "http://www.oasis-open.org/docbook/xml/4.5/docbookx.dtd" [
   4   <!ENTITY % general-entities SYSTEM "../general.ent">
   5   %general-entities;
   6 ]>
   7
   8 <sect1 id="ch-system-glibc" role="wrap">
   9   <?dbhtml filename="glibc.html"?>
  10
  11   <sect1info condition="script">
  12     <productname>glibc</productname>
  13     <productnumber>&glibc-version;</productnumber>
  14     <address>&glibc-url;</address>
  15   </sect1info>
  16
  17   <title>Glibc-&glibc-version;</title>
  18
  19   <indexterm zone="ch-system-glibc">
  20     <primary sortas="a-Glibc">Glibc</primary>
  21   </indexterm>
  22
  23   <sect2 role="package">
  24     <title/>
  25
  26     <para>The Glibc package contains the main C library. This library provides
  27     the basic routines for allocating memory, searching directories, opening and
  28     closing files, reading and writing files, string handling, pattern matching,
  29     arithmetic, and so on.</para>
  30
  31     <segmentedlist>
  32       <segtitle>&buildtime;</segtitle>
  33       <segtitle>&diskspace;</segtitle>
  34
  35       <seglistitem>
  36         <seg>&glibc-ch6-sbu;</seg>
  37         <seg>&glibc-ch6-du;</seg>
  38       </seglistitem>
  39     </segmentedlist>
  40
  41   </sect2>
  42
  43   <sect2 role="installation">
  44     <title>Installation of Glibc</title>
  45
  46     <note>
  47       <para>Some packages outside of LFS suggest installing GNU libiconv in
  48       order to translate data from one encoding to another. The project's
  49       home page (<ulink url="http://www.gnu.org/software/libiconv/"/>) says
  50       <quote>This library provides an <function>iconv()</function>
  51       implementation, for use on systems which don't have one, or whose
  52       implementation cannot convert from/to Unicode.</quote> Glibc provides
  53       an <function>iconv()</function> implementation and can convert from/to
  54       Unicode, therefore libiconv is not required on an LFS system.</para>
  55     </note>
  56     <para>Some of the Glibc programs use non-FHS compilant
  57     <filename class="directory">/var/db</filename> directory to store
  58     their runtime data. Apply the following patch to make such programs
  59     store their runtime data in the FHS-compliant locations:</para>
  60
  61 <screen><userinput remap="pre">patch -Np1 -i ../&glibc-fhs-patch;</userinput></screen>
  62     <para>The Glibc build system is self-contained and will install
  63     perfectly, even though the compiler specs file and linker are still
  64     pointing at <filename class="directory">/tools</filename>. The specs
  65     and linker cannot be adjusted before the Glibc install because the
  66     Glibc autoconf tests would give false results and defeat the goal
  67     of achieving a clean build.</para>
  68
  69     <para>Now, fix a build problem that affects i386 systems:</para>
  70
  71 <screen><userinput remap="pre">patch -Np1 -i ../&glibc-upstream-patch;</userinput></screen>
  72
  73     <para>The Glibc documentation recommends building Glibc outside of the source
  74     directory in a dedicated build directory:</para>
  75
  76 <screen><userinput remap="pre">mkdir -v ../glibc-build
  77 cd ../glibc-build</userinput></screen>
  78
  79     <para>Prepare Glibc for compilation:</para>
  80
  81 <screen><userinput remap="configure">../glibc-&glibc-version;/configure    \
  82     --prefix=/usr          \
  83     --disable-profile      \
  84     --enable-kernel=&min-kernel; \
  85     --enable-obsolete-rpc</userinput></screen>
  86
  87     <para>Compile the package:</para>
  88
  89 <screen><userinput remap="make">make</userinput></screen>
  90
  91     <important>
  92       <para>In this section, the test suite for Glibc is considered critical.
  93       Do not skip it under any circumstance.</para>
  94     </important>
  95
  96     <para>Generally a few tests do not pass, but you can generally ignore
  97     any of the test failures listed below. Now test the build results:</para>
  98
  99 <screen><userinput remap="test">make check</userinput></screen>
 100
 101     <para>You will probably see some test failures.  The Glibc test suite is
 102     somewhat dependent on the host system.  This is a list of the most common
 103     issues seen for this version of LFS:</para>
 104
 105     <itemizedlist>
 106
 107       <listitem>
 108         <para><emphasis>posix/tst-getaddrinfo4</emphasis> will always fail
 109         due to not having the necessary network applications when the tests are
 110         run.</para>
 111       </listitem>
 112
 113       <listitem>
 114         <para>The <emphasis>tst/tst-cputimer1</emphasis> and
 115         <emphasis>rt/tst-cpuclock2</emphasis> tests have been known to
 116         fail.  The reason is not completely understood, but indications are
 117         that minor timing issues can trigger these failures.</para>
 118       </listitem>
 119
 120       <listitem>
 121         <para>The math tests sometimes fail when running on
 122         systems where the CPU is not a relatively new genuine Intel or
 123         authentic AMD processor.</para>
 124       </listitem>
 125 <!--
 126       <listitem>
 127         <para>When running on older and slower hardware or on systems under
 128         load, some tests can fail because of test timeouts being exceeded.
 129         Modifying the make check command to set a TIMEOUTFACTOR is reported to
 130         help eliminate these errors (e.g. <command>TIMEOUTFACTOR=16
 131         make -k check</command>).</para>
 132       </listitem>
 133 -->
 134 <!--
 135       <listitem>
 136         <para>libio/tst-ftell-partial-wide.out fails because it needs a locale
 137         that has not yet been generated.</para>
 138       </listitem>
 139 -->
 140       <listitem>
 141         <para>The <emphasis>elf/tst-protected1a</emphasis> and
 142         <emphasis>elf/tst-protected1b</emphasis> tests are known to
 143         fail with the current stable version of binutils.</para>
 144       </listitem>
 145
 146       <listitem>
 147         <para>Other tests known to fail on some architectures are
 148         malloc/tst-malloc-usable and nptl/tst-cleanupx4. </para>
 149       </listitem>
 150
 151     </itemizedlist>
 152
 153     <para>Though it is a harmless message, the install stage of Glibc will
 154     complain about the absence of <filename>/etc/ld.so.conf</filename>.
 155     Prevent this warning with:</para>
 156
 157 <screen><userinput remap="install">touch /etc/ld.so.conf</userinput></screen>
 158
 159     <para>Install the package:</para>
 160
 161 <screen><userinput remap="install">make install</userinput></screen>
 162
 163     <para>Install the configuration file and runtime directory for
 164     <command>nscd</command>:</para>
 165
 166 <screen><userinput remap="install">cp -v ../glibc-&glibc-version;/nscd/nscd.conf /etc/nscd.conf
 167 mkdir -pv /var/cache/nscd</userinput></screen>
 168
 169     <para>Install the systemd support files for <command>nscd</command>:</para>
 170
 171 <screen><userinput remap="install">install -v -Dm644 ../glibc-&glibc-version;/nscd/nscd.tmpfiles /usr/lib/tmpfiles.d/nscd.conf
 172 install -v -Dm644 ../glibc-&glibc-version;/nscd/nscd.service /lib/systemd/system/nscd.service</userinput></screen>
 173
 174     <para>The locales that can make the system respond in a different language
 175     were not installed by the above command. None of the locales are required,
 176     but if some of them are missing, test suites of the future packages would
 177     skip important testcases.</para>
 178
 179     <para>Individual locales can be installed using the
 180     <command>localedef</command> program. E.g., the first
 181     <command>localedef</command> command below combines the
 182     <filename>/usr/share/i18n/locales/cs_CZ</filename>
 183     charset-independent locale definition with the
 184     <filename>/usr/share/i18n/charmaps/UTF-8.gz</filename>
 185     charmap definition and appends the result to the
 186     <filename>/usr/lib/locale/locale-archive</filename> file.
 187     The following instructions will install the minimum set of
 188     locales necessary for the optimal coverage of tests:</para>
 189
 190 <screen role="nodump"><userinput remap="locale-test">mkdir -pv /usr/lib/locale
 191 localedef -i cs_CZ -f UTF-8 cs_CZ.UTF-8
 192 localedef -i de_DE -f ISO-8859-1 de_DE
 193 localedef -i de_DE@euro -f ISO-8859-15 de_DE@euro
 194 localedef -i de_DE -f UTF-8 de_DE.UTF-8
 195 localedef -i en_GB -f UTF-8 en_GB.UTF-8
 196 localedef -i en_HK -f ISO-8859-1 en_HK
 197 localedef -i en_PH -f ISO-8859-1 en_PH
 198 localedef -i en_US -f ISO-8859-1 en_US
 199 localedef -i en_US -f UTF-8 en_US.UTF-8
 200 localedef -i es_MX -f ISO-8859-1 es_MX
 201 localedef -i fa_IR -f UTF-8 fa_IR
 202 localedef -i fr_FR -f ISO-8859-1 fr_FR
 203 localedef -i fr_FR@euro -f ISO-8859-15 fr_FR@euro
 204 localedef -i fr_FR -f UTF-8 fr_FR.UTF-8
 205 localedef -i it_IT -f ISO-8859-1 it_IT
 206 localedef -i it_IT -f UTF-8 it_IT.UTF-8
 207 localedef -i ja_JP -f EUC-JP ja_JP
 208 localedef -i ru_RU -f KOI8-R ru_RU.KOI8-R
 209 localedef -i ru_RU -f UTF-8 ru_RU.UTF-8
 210 localedef -i tr_TR -f UTF-8 tr_TR.UTF-8
 211 localedef -i zh_CN -f GB18030 zh_CN.GB18030</userinput></screen>
 212
 213     <para>In addition, install the locale for your own country, language and
 214     character set.</para>
 215
 216     <para>Alternatively, install all locales listed in the
 217     <filename>glibc-&glibc-version;/localedata/SUPPORTED</filename> file
 218     (it includes every locale listed above and many more) at once with the
 219     following time-consuming command:</para>
 220
 221 <screen><userinput remap="locale-full">make localedata/install-locales</userinput></screen>
 222
 223     <para>Then use the <command>localedef</command> command to create and
 224     install locales not listed in the
 225     <filename>glibc-&glibc-version;/localedata/SUPPORTED</filename> file
 226     in the unlikely case you need them.</para>
 227
 228   </sect2>
 229
 230   <sect2 id="conf-glibc" role="configuration">
 231     <title>Configuring Glibc</title>
 232
 233     <indexterm zone="conf-glibc">
 234       <primary sortas="e-/etc/nsswitch.conf">/etc/nsswitch.conf</primary>
 235     </indexterm>
 236
 237     <indexterm zone="conf-glibc">
 238       <primary sortas="e-/etc/localtime">/etc/localtime</primary>
 239     </indexterm>
 240
 241   <sect3>
 242   <title>Adding nsswitch.conf</title>
 243
 244     <para>The <filename>/etc/nsswitch.conf</filename> file needs to be created
 245     because the Glibc defaults do not work well in a networked environment.
 246     </para>
 247
 248     <para>Create a new file <filename>/etc/nsswitch.conf</filename> by running the
 249     following:</para>
 250
 251 <screen><userinput>cat &gt; /etc/nsswitch.conf &lt;&lt; "EOF"
 252 <literal># Begin /etc/nsswitch.conf
 253
 254 passwd: files
 255 group: files
 256 shadow: files
 257
 258 hosts: files dns myhostname
 259 networks: files
 260
 261 protocols: files
 262 services: files
 263 ethers: files
 264 rpc: files
 265
 266 # End /etc/nsswitch.conf</literal>
 267 EOF</userinput></screen>
 268
 269     </sect3>
 270
 271     <sect3>
 272     <title>Adding time zone data</title>
 273
 274     <para>Install and set up the timezone data with the following:</para>
 275 <screen><userinput>tar -xf ../tzdata&tzdata-version;.tar.gz
 276
 277 ZONEINFO=/usr/share/zoneinfo
 278 mkdir -pv $ZONEINFO/{posix,right}
 279
 280 for tz in etcetera southamerica northamerica europe africa antarctica  \
 281           asia australasia backward pacificnew systemv; do
 282     zic -L /dev/null   -d $ZONEINFO       -y "sh yearistype.sh" ${tz}
 283     zic -L /dev/null   -d $ZONEINFO/posix -y "sh yearistype.sh" ${tz}
 284     zic -L leapseconds -d $ZONEINFO/right -y "sh yearistype.sh" ${tz}
 285 done
 286
 287 cp -v zone.tab zone1970.tab iso3166.tab $ZONEINFO
 288 zic -d $ZONEINFO -p America/New_York
 289 unset ZONEINFO</userinput></screen>
 290
 291     <variablelist>
 292       <title>The meaning of the zic commands:</title>
 293
 294       <varlistentry>
 295         <term><parameter>zic -L /dev/null ...</parameter></term>
 296         <listitem>
 297           <para>This creates posix timezones, without any leap seconds.  It is
 298           conventional to put these in both
 299           <filename class="directory">zoneinfo</filename> and
 300           <filename class="directory">zoneinfo/posix</filename>. It is
 301           necessary to put the POSIX timezones in
 302           <filename class="directory">zoneinfo</filename>, otherwise various
 303           test-suites will report errors. On an embedded system, where space is
 304           tight and you do not intend to ever update the timezones, you could save
 305           1.9MB by not using the <filename class="directory">posix</filename>
 306           directory, but some applications or test-suites might produce some
 307           failures.</para>
 308         </listitem>
 309       </varlistentry>
 310       <varlistentry>
 311         <term><parameter>zic -L leapseconds ...</parameter></term>
 312         <listitem>
 313           <para>This creates right timezones, including leap seconds. On an
 314           embedded system, where space is tight and you do not intend to
 315           ever update the timezones, or care about the correct time, you could
 316           save 1.9MB by omitting the <filename class="directory">right</filename>
 317           directory.</para>
 318         </listitem>
 319       </varlistentry>
 320       <varlistentry>
 321         <term><parameter>zic ... -p ...</parameter></term>
 322         <listitem>
 323           <para>This creates the <filename>posixrules</filename> file. We use
 324           New York because POSIX requires the daylight savings time rules
 325           to be in accordance with US rules.</para>
 326         </listitem>
 327       </varlistentry>
 328     </variablelist>
 329
 330
 331     <para>One way to determine the local time zone is to run the following
 332     script:</para>
 333
 334 <screen role="nodump"><userinput>tzselect</userinput></screen>
 335
 336     <para>After answering a few questions about the location, the script will
 337     output the name of the time zone (e.g.,
 338     <emphasis>America/Edmonton</emphasis>). There are also some other possible
 339     timezones listed in <filename
 340     class='directory'>/usr/share/zoneinfo</filename> such as
 341     <emphasis>Canada/Eastern</emphasis> or <emphasis>EST5EDT</emphasis> that
 342     are not identified by the script but can be used.</para>
 343
 344     <para>Then create the <filename>/etc/localtime</filename> file by
 345     running:</para>
 346
 347 <screen><userinput>ln -sfv /usr/share/zoneinfo/<replaceable>&lt;xxx&gt;</replaceable> /etc/localtime</userinput></screen>
 348
 349     <para>Replace <replaceable>&lt;xxx&gt;</replaceable> with the name of the
 350     time zone selected (e.g., Canada/Eastern).</para>
 351
 352   </sect3>
 353
 354   <sect3 id="conf-ld" role="configuration">
 355     <title>Configuring the Dynamic Loader</title>
 356
 357     <indexterm zone="conf-ld">
 358       <primary sortas="e-/etc/ld.so.conf">/etc/ld.so.conf</primary>
 359     </indexterm>
 360
 361     <para>By default, the dynamic loader (<filename
 362     class="libraryfile">/lib/ld-linux.so.2</filename>) searches through
 363     <filename class="directory">/lib</filename> and <filename
 364     class="directory">/usr/lib</filename> for dynamic libraries that are
 365     needed by programs as they are run. However, if there are libraries in
 366     directories other than <filename class="directory">/lib</filename> and
 367     <filename class="directory">/usr/lib</filename>, these need to be added
 368     to the <filename>/etc/ld.so.conf</filename> file in order for the
 369     dynamic loader to find them. Two directories that are commonly known
 370     to contain additional libraries are <filename
 371     class="directory">/usr/local/lib</filename> and <filename
 372     class="directory">/opt/lib</filename>, so add those directories to the
 373     dynamic loader's search path.</para>
 374
 375     <para>Create a new file <filename>/etc/ld.so.conf</filename> by running the
 376     following:</para>
 377
 378 <screen><userinput>cat &gt; /etc/ld.so.conf &lt;&lt; "EOF"
 379 <literal># Begin /etc/ld.so.conf
 380 /usr/local/lib
 381 /opt/lib
 382 </literal>
 383 EOF</userinput></screen>
 384
 385   <para>If desired, the dynamic loader can also search a directory and
 386   include the contents of files found there.  Generally the files in
 387   this include directory are one line specifying the desired library path.
 388   To add this capability run the following commands:</para>
 389
 390 <screen role="nodump"><userinput>cat &gt;&gt; /etc/ld.so.conf &lt;&lt; "EOF"
 391 <literal># Add an include directory
 392 include /etc/ld.so.conf.d/*.conf
 393 </literal>
 394 EOF
 395 mkdir -pv /etc/ld.so.conf.d</userinput></screen>
 396
 397   </sect3>
 398   </sect2>
 399
 400   <sect2 id="contents-glibc" role="content">
 401     <title>Contents of Glibc</title>
 402
 403     <segmentedlist>
 404       <segtitle>Installed programs</segtitle>
 405       <segtitle>Installed libraries</segtitle>
 406       <segtitle>Installed directories</segtitle>
 407
 408       <seglistitem>
 409         <seg>catchsegv, gencat, getconf, getent, iconv, iconvconfig, ldconfig,
 410         ldd, lddlibc4, locale, localedef, makedb, mtrace, nscd, pcprofiledump,
 411         pldd, rpcgen, sln, sotruss, sprof, tzselect, xtrace,
 412         zdump, and zic</seg>
 413         <seg>ld-&glibc-version;.so, libBrokenLocale.{a,so}, libSegFault.so, libanl.{a,so},
 414         libc.{a,so}, libc_nonshared.a, libcidn.so,
 415         libcrypt.{a,so}, libdl.{a,so}, libg.a, libieee.a, libm.{a,so},
 416         libmcheck.a, libmemusage.so, libnsl.{a,so}, libnss_compat.so,
 417         libnss_dns.so, libnss_files.so, libnss_hesiod.so, libnss_nis.so,
 418         libnss_nisplus.so, libpcprofile.so, libpthread.{a,so},
 419         libpthread_nonshared.a, libresolv.{a,so}, librpcsvc.a, librt.{a,so},
 420         libthread_db.so, and libutil.{a,so}</seg>
 421         <seg>/usr/include/arpa, /usr/include/bits, /usr/include/gnu,
 422         /usr/include/net, /usr/include/netash, /usr/include/netatalk,
 423         /usr/include/netax25, /usr/include/neteconet, /usr/include/netinet,
 424         /usr/include/netipx, /usr/include/netiucv, /usr/include/netpacket,
 425         /usr/include/netrom, /usr/include/netrose, /usr/include/nfs,
 426         /usr/include/protocols, /usr/include/rpc, /usr/include/rpcsvc,
 427         /usr/include/sys, /usr/lib/audit, /usr/lib/gconv, /usr/lib/locale,
 428         /usr/libexec/getconf, /usr/share/i18n, /usr/share/zoneinfo,
 429         /var/cache/nscd, and /var/lib/nss_db</seg>
 430       </seglistitem>
 431     </segmentedlist>
 432
 433     <variablelist>
 434       <bridgehead renderas="sect3">Short Descriptions</bridgehead>
 435       <?dbfo list-presentation="list"?>
 436       <?dbhtml list-presentation="table"?>
 437
 438       <varlistentry id="catchsegv">
 439         <term><command>catchsegv</command></term>
 440         <listitem>
 441           <para>Can be used to create a stack trace when a program
 442           terminates with a segmentation fault</para>
 443           <indexterm zone="ch-system-glibc catchsegv">
 444             <primary sortas="b-catchsegv">catchsegv</primary>
 445           </indexterm>
 446         </listitem>
 447       </varlistentry>
 448
 449       <varlistentry id="gencat">
 450         <term><command>gencat</command></term>
 451         <listitem>
 452           <para>Generates message catalogues</para>
 453           <indexterm zone="ch-system-glibc gencat">
 454             <primary sortas="b-gencat">gencat</primary>
 455           </indexterm>
 456         </listitem>
 457       </varlistentry>
 458
 459       <varlistentry id="getconf">
 460         <term><command>getconf</command></term>
 461         <listitem>
 462           <para>Displays the system configuration values for file system
 463           specific variables</para>
 464           <indexterm zone="ch-system-glibc getconf">
 465             <primary sortas="b-getconf">getconf</primary>
 466           </indexterm>
 467         </listitem>
 468       </varlistentry>
 469
 470       <varlistentry id="getent">
 471         <term><command>getent</command></term>
 472         <listitem>
 473           <para>Gets entries from an administrative database</para>
 474           <indexterm zone="ch-system-glibc getent">
 475             <primary sortas="b-getent">getent</primary>
 476           </indexterm>
 477         </listitem>
 478       </varlistentry>
 479
 480       <varlistentry id="iconv">
 481         <term><command>iconv</command></term>
 482         <listitem>
 483           <para>Performs character set conversion</para>
 484           <indexterm zone="ch-system-glibc iconv">
 485             <primary sortas="b-iconv">iconv</primary>
 486           </indexterm>
 487         </listitem>
 488       </varlistentry>
 489
 490       <varlistentry id="iconvconfig">
 491         <term><command>iconvconfig</command></term>
 492         <listitem>
 493           <para>Creates fastloading <command>iconv</command> module configuration
 494           files</para>
 495           <indexterm zone="ch-system-glibc iconvconfig">
 496             <primary sortas="b-iconvconfig">iconvconfig</primary>
 497           </indexterm>
 498         </listitem>
 499       </varlistentry>
 500
 501       <varlistentry id="ldconfig">
 502         <term><command>ldconfig</command></term>
 503         <listitem>
 504           <para>Configures the dynamic linker runtime bindings</para>
 505           <indexterm zone="ch-system-glibc ldconfig">
 506             <primary sortas="b-ldconfig">ldconfig</primary>
 507           </indexterm>
 508         </listitem>
 509       </varlistentry>
 510
 511       <varlistentry id="ldd">
 512         <term><command>ldd</command></term>
 513         <listitem>
 514           <para>Reports which shared libraries are required
 515           by each given program or shared library</para>
 516           <indexterm zone="ch-system-glibc ldd">
 517             <primary sortas="b-ldd">ldd</primary>
 518           </indexterm>
 519         </listitem>
 520       </varlistentry>
 521
 522       <varlistentry id="lddlibc4">
 523         <term><command>lddlibc4</command></term>
 524         <listitem>
 525           <para>Assists <command>ldd</command> with object files</para>
 526           <indexterm zone="ch-system-glibc lddlibc4">
 527             <primary sortas="b-lddlibc4">lddlibc4</primary>
 528           </indexterm>
 529         </listitem>
 530       </varlistentry>
 531
 532       <varlistentry id="locale">
 533         <term><command>locale</command></term>
 534         <listitem>
 535           <para>Prints various information about the current locale</para>
 536           <indexterm zone="ch-system-glibc locale">
 537             <primary sortas="b-locale">locale</primary>
 538           </indexterm>
 539         </listitem>
 540       </varlistentry>
 541
 542       <varlistentry id="localedef">
 543         <term><command>localedef</command></term>
 544         <listitem>
 545           <para>Compiles locale specifications</para>
 546           <indexterm zone="ch-system-glibc localedef">
 547             <primary sortas="b-localedef">localedef</primary>
 548           </indexterm>
 549         </listitem>
 550       </varlistentry>
 551
 552       <varlistentry id="makedb">
 553         <term><command>makedb</command></term>
 554         <listitem>
 555           <para>Creates a simple database from textual input</para>
 556           <indexterm zone="ch-system-glibc makedb">
 557             <primary sortas="b-makedb">makedb</primary>
 558           </indexterm>
 559         </listitem>
 560       </varlistentry>
 561
 562       <varlistentry id="mtrace">
 563         <term><command>mtrace</command></term>
 564         <listitem>
 565           <para>Reads and interprets a memory trace file and displays a summary
 566           in human-readable format</para>
 567           <indexterm zone="ch-system-glibc mtrace">
 568             <primary sortas="b-mtrace">mtrace</primary>
 569           </indexterm>
 570         </listitem>
 571       </varlistentry>
 572
 573       <varlistentry id="nscd">
 574         <term><command>nscd</command></term>
 575         <listitem>
 576           <para>A daemon that provides a cache for the most common name
 577           service requests</para>
 578           <indexterm zone="ch-system-glibc nscd">
 579             <primary sortas="b-nscd">nscd</primary>
 580           </indexterm>
 581         </listitem>
 582       </varlistentry>
 583
 584       <varlistentry id="pcprofiledump">
 585         <term><command>pcprofiledump</command></term>
 586         <listitem>
 587           <para>Dumps information generated by PC profiling</para>
 588           <indexterm zone="ch-system-glibc pcprofiledump">
 589             <primary sortas="b-pcprofiledump">pcprofiledump</primary>
 590           </indexterm>
 591         </listitem>
 592       </varlistentry>
 593
 594       <varlistentry id="pldd">
 595         <term><command>pldd</command></term>
 596         <listitem>
 597           <para>Lists dynamic shared objects used by running processes</para>
 598           <indexterm zone="ch-system-glibc pldd">
 599             <primary sortas="b-pldd">pldd</primary>
 600           </indexterm>
 601         </listitem>
 602       </varlistentry>
 603 <!--
 604       <varlistentry id="pt_chown">
 605         <term><command>pt_chown</command></term>
 606         <listitem>
 607           <para>A helper program for <command>grantpt</command> to set the owner,
 608           group and access permissions of a slave pseudo terminal</para>
 609           <indexterm zone="ch-system-glibc pt_chown">
 610             <primary sortas="b-pt_chown">pt_chown</primary>
 611           </indexterm>
 612         </listitem>
 613       </varlistentry>
 614 -->
 615       <varlistentry id="rpcgen">
 616         <term><command>rpcgen</command></term>
 617         <listitem>
 618           <para>Generates C code to implement the Remote Procedure Call (RPC)
 619           protocol</para>
 620           <indexterm zone="ch-system-glibc rpcgen">
 621             <primary sortas="b-rpcgen">rpcgen</primary>
 622           </indexterm>
 623         </listitem>
 624       </varlistentry>
 625
 626       <varlistentry id="sln">
 627         <term><command>sln</command></term>
 628         <listitem>
 629           <para>A statically linked <command>ln</command> program</para>
 630           <indexterm zone="ch-system-glibc sln">
 631             <primary sortas="b-sln">sln</primary>
 632           </indexterm>
 633         </listitem>
 634       </varlistentry>
 635
 636       <varlistentry id="sotruss">
 637         <term><command>sotruss</command></term>
 638         <listitem>
 639           <para>Traces shared library procedure calls of a specified command</para>
 640           <indexterm zone="ch-system-glibc sotruss">
 641             <primary sortas="b-sotruss">sotruss</primary>
 642           </indexterm>
 643         </listitem>
 644       </varlistentry>
 645
 646       <varlistentry id="sprof">
 647         <term><command>sprof</command></term>
 648         <listitem>
 649           <para>Reads and displays shared object profiling data</para>
 650           <indexterm zone="ch-system-glibc sprof">
 651             <primary sortas="b-sprof">sprof</primary>
 652           </indexterm>
 653         </listitem>
 654       </varlistentry>
 655
 656       <varlistentry id="tzselect">
 657         <term><command>tzselect</command></term>
 658         <listitem>
 659           <para>Asks the user about the location of the system and reports
 660           the corresponding time zone description</para>
 661           <indexterm zone="ch-system-glibc tzselect">
 662             <primary sortas="b-tzselect">tzselect</primary>
 663           </indexterm>
 664         </listitem>
 665       </varlistentry>
 666
 667       <varlistentry id="xtrace">
 668         <term><command>xtrace</command></term>
 669         <listitem>
 670           <para>Traces the execution of a program by printing the currently
 671           executed function</para>
 672           <indexterm zone="ch-system-glibc xtrace">
 673             <primary sortas="b-xtrace">xtrace</primary>
 674           </indexterm>
 675         </listitem>
 676       </varlistentry>
 677
 678       <varlistentry id="zdump">
 679         <term><command>zdump</command></term>
 680         <listitem>
 681           <para>The time zone dumper</para>
 682           <indexterm zone="ch-system-glibc zdump">
 683             <primary sortas="b-zdump">zdump</primary>
 684           </indexterm>
 685         </listitem>
 686       </varlistentry>
 687
 688       <varlistentry id="zic">
 689         <term><command>zic</command></term>
 690         <listitem>
 691           <para>The time zone compiler</para>
 692           <indexterm zone="ch-system-glibc zic">
 693             <primary sortas="b-zic">zic</primary>
 694           </indexterm>
 695         </listitem>
 696       </varlistentry>
 697
 698       <varlistentry id="ld.so">
 699         <term><filename class="libraryfile">ld-&glibc-version;.so</filename></term>
 700         <listitem>
 701           <para>The helper program for shared library executables</para>
 702           <indexterm zone="ch-system-glibc ld.so">
 703             <primary sortas="c-ld.so">ld-&glibc-version;.so</primary>
 704           </indexterm>
 705         </listitem>
 706       </varlistentry>
 707
 708       <varlistentry id="libBrokenLocale">
 709         <term><filename class="libraryfile">libBrokenLocale</filename></term>
 710         <listitem>
 711           <para>Used internally by Glibc as a gross hack to get broken programs
 712           (e.g., some Motif applications) running. See comments in
 713           <filename>glibc-&glibc-version;/locale/broken_cur_max.c</filename>
 714           for more information</para>
 715           <indexterm zone="ch-system-glibc libBrokenLocale">
 716             <primary sortas="c-libBrokenLocale">libBrokenLocale</primary>
 717           </indexterm>
 718         </listitem>
 719       </varlistentry>
 720
 721       <varlistentry id="libSegFault">
 722         <term><filename class="libraryfile">libSegFault</filename></term>
 723         <listitem>
 724           <para>The segmentation fault signal handler, used by
 725           <command>catchsegv</command></para>
 726           <indexterm zone="ch-system-glibc libSegFault">
 727             <primary sortas="c-libSegFault">libSegFault</primary>
 728           </indexterm>
 729         </listitem>
 730       </varlistentry>
 731
 732       <varlistentry id="libanl">
 733         <term><filename class="libraryfile">libanl</filename></term>
 734         <listitem>
 735           <para>An asynchronous name lookup library</para>
 736           <indexterm zone="ch-system-glibc libanl">
 737             <primary sortas="c-libanl">libanl</primary>
 738           </indexterm>
 739         </listitem>
 740       </varlistentry>
 741
 742       <varlistentry id="libc">
 743         <term><filename class="libraryfile">libc</filename></term>
 744         <listitem>
 745           <para>The main C library</para>
 746           <indexterm zone="ch-system-glibc libc">
 747             <primary sortas="c-libc">libc</primary>
 748           </indexterm>
 749         </listitem>
 750       </varlistentry>
 751
 752       <varlistentry id="libcidn">
 753         <term><filename class="libraryfile">libcidn</filename></term>
 754         <listitem>
 755           <para>Used internally by Glibc for handling internationalized domain
 756           names in the <function>getaddrinfo()</function> function</para>
 757           <indexterm zone="ch-system-glibc libcidn">
 758             <primary sortas="c-libcidn">libcidn</primary>
 759           </indexterm>
 760         </listitem>
 761       </varlistentry>
 762
 763       <varlistentry id="libcrypt">
 764         <term><filename class="libraryfile">libcrypt</filename></term>
 765         <listitem>
 766           <para>The cryptography library</para>
 767           <indexterm zone="ch-system-glibc libcrypt">
 768             <primary sortas="c-libcrypt">libcrypt</primary>
 769           </indexterm>
 770         </listitem>
 771       </varlistentry>
 772
 773       <varlistentry id="libdl">
 774         <term><filename class="libraryfile">libdl</filename></term>
 775         <listitem>
 776           <para>The dynamic linking interface library</para>
 777           <indexterm zone="ch-system-glibc libdl">
 778             <primary sortas="c-libdl">libdl</primary>
 779           </indexterm>
 780         </listitem>
 781       </varlistentry>
 782
 783       <varlistentry id="libg">
 784         <term><filename class="libraryfile">libg</filename></term>
 785         <listitem>
 786           <para>Dummy library containing no functions. Previously was a runtime
 787           library for <command>g++</command></para>
 788           <indexterm zone="ch-system-glibc libg">
 789             <primary sortas="c-libg">libg</primary>
 790           </indexterm>
 791         </listitem>
 792       </varlistentry>
 793
 794       <varlistentry id="libieee">
 795         <term><filename class="libraryfile">libieee</filename></term>
 796         <listitem>
 797           <para>Linking in this module forces error handling rules for math
 798           functions as defined by the Institute of Electrical and Electronic
 799           Engineers (IEEE). The default is POSIX.1 error handling</para>
 800           <indexterm zone="ch-system-glibc libieee">
 801             <primary sortas="c-libieee">libieee</primary>
 802           </indexterm>
 803         </listitem>
 804       </varlistentry>
 805
 806       <varlistentry id="libm">
 807         <term><filename class="libraryfile">libm</filename></term>
 808         <listitem>
 809           <para>The mathematical library</para>
 810           <indexterm zone="ch-system-glibc libm">
 811             <primary sortas="c-libm">libm</primary>
 812           </indexterm>
 813         </listitem>
 814       </varlistentry>
 815
 816       <varlistentry id="libmcheck">
 817         <term><filename class="libraryfile">libmcheck</filename></term>
 818         <listitem>
 819           <para>Turns on memory allocation checking when linked to</para>
 820           <indexterm zone="ch-system-glibc libmcheck">
 821             <primary sortas="c-libmcheck">libmcheck</primary>
 822           </indexterm>
 823         </listitem>
 824       </varlistentry>
 825
 826       <varlistentry id="libmemusage">
 827         <term><filename class="libraryfile">libmemusage</filename></term>
 828         <listitem>
 829           <para>Used by <command>memusage</command> to help collect
 830           information about the memory usage of a program</para>
 831           <indexterm zone="ch-system-glibc libmemusage">
 832             <primary sortas="c-libmemusage">libmemusage</primary>
 833           </indexterm>
 834         </listitem>
 835       </varlistentry>
 836
 837       <varlistentry id="libnsl">
 838         <term><filename class="libraryfile">libnsl</filename></term>
 839         <listitem>
 840           <para>The network services library</para>
 841           <indexterm zone="ch-system-glibc libnsl">
 842             <primary sortas="c-libnsl">libnsl</primary>
 843           </indexterm>
 844         </listitem>
 845       </varlistentry>
 846
 847       <varlistentry id="libnss">
 848         <term><filename class="libraryfile">libnss</filename></term>
 849         <listitem>
 850           <para>The Name Service Switch libraries, containing functions for
 851           resolving host names, user names, group names, aliases, services,
 852           protocols, etc.</para>
 853           <indexterm zone="ch-system-glibc libnss">
 854             <primary sortas="c-libnss">libnss</primary>
 855           </indexterm>
 856         </listitem>
 857       </varlistentry>
 858
 859       <varlistentry id="libpcprofile">
 860         <term><filename class="libraryfile">libpcprofile</filename></term>
 861         <listitem>
 862           <para>Contains profiling functions used to track the amount of CPU
 863           time spent in specific source code lines</para>
 864           <indexterm zone="ch-system-glibc libpcprofile">
 865             <primary sortas="c-libpcprofile">libpcprofile</primary>
 866           </indexterm>
 867         </listitem>
 868       </varlistentry>
 869
 870       <varlistentry id="libpthread">
 871         <term><filename class="libraryfile">libpthread</filename></term>
 872         <listitem>
 873           <para>The POSIX threads library</para>
 874           <indexterm zone="ch-system-glibc libpthread">
 875             <primary sortas="c-libpthread">libpthread</primary>
 876           </indexterm>
 877         </listitem>
 878       </varlistentry>
 879
 880       <varlistentry id="libresolv">
 881         <term><filename class="libraryfile">libresolv</filename></term>
 882         <listitem>
 883           <para>Contains functions for creating, sending, and interpreting
 884           packets to the Internet domain name servers</para>
 885           <indexterm zone="ch-system-glibc libresolv">
 886             <primary sortas="c-libresolv">libresolv</primary>
 887           </indexterm>
 888         </listitem>
 889       </varlistentry>
 890
 891       <varlistentry id="librpcsvc">
 892         <term><filename class="libraryfile">librpcsvc</filename></term>
 893         <listitem>
 894           <para>Contains functions providing miscellaneous RPC services</para>
 895           <indexterm zone="ch-system-glibc librpcsvc">
 896             <primary sortas="c-librpcsvc">librpcsvc</primary>
 897           </indexterm>
 898         </listitem>
 899       </varlistentry>
 900
 901       <varlistentry id="librt">
 902         <term><filename class="libraryfile">librt</filename></term>
 903         <listitem>
 904           <para>Contains functions providing most of the interfaces specified
 905           by the POSIX.1b Realtime Extension</para>
 906           <indexterm zone="ch-system-glibc librt">
 907             <primary sortas="c-librt">librt</primary>
 908           </indexterm>
 909         </listitem>
 910       </varlistentry>
 911
 912       <varlistentry id="libthread_db">
 913         <term><filename class="libraryfile">libthread_db</filename></term>
 914         <listitem>
 915           <para>Contains functions useful for building debuggers for
 916           multi-threaded programs</para>
 917           <indexterm zone="ch-system-glibc libthread_db">
 918             <primary sortas="c-libthread_db">libthread_db</primary>
 919           </indexterm>
 920         </listitem>
 921       </varlistentry>
 922
 923       <varlistentry id="libutil">
 924         <term><filename class="libraryfile">libutil</filename></term>
 925         <listitem>
 926           <para>Contains code for <quote>standard</quote> functions used in
 927           many different Unix utilities</para>
 928           <indexterm zone="ch-system-glibc libutil">
 929             <primary sortas="c-libutil">libutil</primary>
 930           </indexterm>
 931         </listitem>
 932       </varlistentry>
 933
 934     </variablelist>
 935
 936   </sect2>
 937
 938 </sect1>