Ticket #2843: glibc.xml

File glibc.xml, 35.6 KB (added by Marcel van den Boer, 14 years ago)

Suggested change

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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
57 <para>The Glibc build system is self-contained and will install
58 perfectly, even though the compiler specs file and linker are still
59 pointing at <filename class="directory">/tools</filename>. The specs
60 and linker cannot be adjusted before the Glibc install because the
61 Glibc autoconf tests would give false results and defeat the goal
62 of achieving a clean build.</para>
63
64<!--
65 This should have been fixed a long time ago.
66
67 <para>In the vi_VN.TCVN locale, <command>bash</command> enters an infinite
68 loop at startup. It is unknown whether this is a <command>bash</command>
69 bug or a Glibc problem. Disable installation of this locale in order to
70 avoid the problem:</para>
71
72<screen><userinput remap="pre">sed -i '/vi_VN.TCVN/d' localedata/SUPPORTED</userinput></screen>
73-->
74
75 <para>When running <command>make install</command>, a script called
76 <filename>test-installation.pl</filename> performs a small sanity test on
77 our newly installed Glibc. However, because our toolchain still points to
78 the <filename class="directory">/tools</filename> directory, the sanity
79 test would be carried out against the wrong Glibc. We can force the script
80 to check the Glibc we have just installed with the following:</para>
81
82<screen><userinput remap="pre">DL=$(readelf -l /bin/sh | sed -n 's@.*interpret.*/tools\(.*\)]$@\1@p')
83sed -i &quot;s|libs -o|libs -L/usr/lib -Wl,-dynamic-linker=$DL -o|&quot; \
84 scripts/test-installation.pl
85unset DL</userinput></screen>
86
87 <para>In addition, there is a bug in the
88 <filename>test-installation.pl</filename> script in that it tries to link
89 a test program to a library that isn't installed by
90 <command>make install</command>. Issue the following <command>sed</command>
91 command to fix it:</para>
92
93 <screen><userinput remap="pre">sed -i -e 's/"db1"/&amp; \&amp;\&amp; $name ne "nss_test1"/' scripts/test-installation.pl</userinput></screen>
94
95 <para>The <command>ldd</command> shell script contains Bash-specific
96 syntax. Change its default program interpreter to <command>/bin/bash</command>
97 in case another <command>/bin/sh</command> is installed as described in the
98 <ulink url="&blfs-root;view/svn/postlfs/shells.html">Shells</ulink>
99 chapter of the BLFS book:</para>
100
101<screen><userinput remap="pre">sed -i 's|@BASH@|/bin/bash|' elf/ldd.bash.in</userinput></screen>
102
103 <para>Fix a bug that prevents Glibc from building with GCC-&gcc-version;:</para>
104
105<screen><userinput remap="pre">patch -Np1 -i ../&glibc-gcc_fix-patch;</userinput></screen>
106
107 <para>Fix a stack imbalance that occurs under some conditions:</para>
108
109<screen><userinput remap="pre">sed -i '195,213 s/PRIVATE_FUTEX/FUTEX_CLOCK_REALTIME/' \
110nptl/sysdeps/unix/sysv/linux/x86_64/pthread_rwlock_timed{rd,wr}lock.S</userinput></screen>
111
112 <para>The Glibc documentation recommends building Glibc outside of the source
113 directory in a dedicated build directory:</para>
114
115<screen><userinput remap="pre">mkdir -v ../glibc-build
116cd ../glibc-build</userinput></screen>
117
118 <para>As in Chapter 5, add the needed compiler flags to CFLAGS for x86 machines.
119 Here, the optimization of the library is also set for the gcc compiler to
120 enhance compilation speed (-pipe) and package performance (-O3).</para>
121
122<screen><userinput remap="configure">case `uname -m` in
123 i?86) echo "CFLAGS += -march=i486 -mtune=native -O3 -pipe" &gt; configparms ;;
124esac</userinput></screen>
125
126 <para>Prepare Glibc for compilation:</para>
127
128<screen><userinput remap="configure">../glibc-&glibc-version;/configure --prefix=/usr \
129 --disable-profile --enable-add-ons \
130 --enable-kernel=2.6.22.5 --libexecdir=/usr/lib/glibc</userinput></screen>
131
132 <variablelist>
133 <title>The meaning of the new configure options:</title>
134
135 <varlistentry>
136 <term><parameter>--libexecdir=/usr/lib/glibc</parameter></term>
137 <listitem>
138 <para>This changes the location of the <command>pt_chown</command>
139 program from its default of <filename
140 class="directory">/usr/libexec</filename> to <filename
141 class="directory">/usr/lib/glibc</filename>.</para>
142 </listitem>
143 </varlistentry>
144
145 </variablelist>
146
147 <para>Compile the package:</para>
148
149<screen><userinput remap="make">make</userinput></screen>
150
151 <important>
152 <para>In this section, the test suite for Glibc is considered critical.
153 Do not skip it under any circumstance.</para>
154 </important>
155
156 <para>Before running the tests, copy a file from the source tree into our
157 build tree to prevent a couple of test failures, then test the
158 results:</para>
159
160<screen><userinput remap="test">cp -v ../glibc-&glibc-version;/iconvdata/gconv-modules iconvdata
161make -k check 2&gt;&amp;1 | tee glibc-check-log
162grep Error glibc-check-log</userinput></screen>
163
164 <para>You will probably see an expected (ignored) failure in the
165 <emphasis>posix/annexc</emphasis> test. In addition the Glibc test suite
166 is somewhat dependent on the host system. This is a list of the most
167 common issues:</para>
168
169 <itemizedlist>
170 <!-- Check again after updating from gcc-4.1.x -->
171 <!-- Haven;t seen this in quite a while <listitem>
172 <para>The <emphasis>nptl/tst-cancel1</emphasis> test will fail when
173 using the 4.1 series of GCC.</para>
174 </listitem> -->
175 <!-- Was true in glibc-2.3.6, rt/tst-cpuclock2 in glibc-2.11.1 -->
176 <listitem>
177
178 <para>The <emphasis>nptl/tst-clock2</emphasis>,
179 <emphasis>nptl/tst-attr3</emphasis>, and
180 <emphasis>rt/tst-cpuclock2</emphasis>
181 tests have been known to fail. The
182 reason is not completely understood, but indications are that minor
183 timing issues can trigger these failures.</para>
184
185 </listitem>
186 <listitem>
187 <para>The math tests sometimes fail when running on
188 systems where the CPU is not a relatively new genuine Intel or
189 authentic AMD processor.</para>
190 </listitem>
191 <listitem>
192 <para>If you have mounted the LFS partition with the
193 <parameter>noatime</parameter> option, the <emphasis>atime</emphasis>
194 test will fail. As mentioned in <xref linkend="space-mounting"/>, do not
195 use the <parameter>noatime</parameter> option while building LFS.</para>
196 </listitem>
197 <listitem>
198 <para>When running on older and slower hardware or on systems under
199 load, some tests can fail because of test timeouts being exceeded.
200 Modifying the make check command to set a TIMEOUTFACTOR is reported to
201 help eliminate these errors (e.g. <command>TIMEOUTFACTOR=16
202 make -k check</command>).</para>
203 </listitem>
204 </itemizedlist>
205
206 <para>Though it is a harmless message, the install stage of Glibc will
207 complain about the absence of <filename>/etc/ld.so.conf</filename>.
208 Prevent this warning with:</para>
209
210<screen><userinput remap="install">touch /etc/ld.so.conf</userinput></screen>
211
212 <para>Install the package:</para>
213
214<screen><userinput remap="install">make install</userinput></screen>
215
216 <para>The locales that can make the system respond in a different language
217 were not installed by the above command. None of the locales are required,
218 but if some of them are missing, test suites of the future packages would
219 skip important testcases.</para>
220
221 <para>Individual locales can be installed using the
222 <command>localedef</command> program. E.g., the first
223 <command>localedef</command> command below combines the
224 <filename>/usr/share/i18n/locales/cs_CZ</filename>
225 charset-independent locale definition with the
226 <filename>/usr/share/i18n/charmaps/UTF-8.gz</filename>
227 charmap definition and appends the result to the
228 <filename>/usr/lib/locale/locale-archive</filename> file.
229 The following instructions will install the minimum set of
230 locales necessary for the optimal coverage of tests:</para>
231
232<screen role="nodump"><userinput remap="locale-test">mkdir -pv /usr/lib/locale
233localedef -i cs_CZ -f UTF-8 cs_CZ.UTF-8
234localedef -i de_DE -f ISO-8859-1 de_DE
235localedef -i de_DE@euro -f ISO-8859-15 de_DE@euro
236localedef -i de_DE -f UTF-8 de_DE.UTF-8
237localedef -i en_HK -f ISO-8859-1 en_HK
238localedef -i en_PH -f ISO-8859-1 en_PH
239localedef -i en_US -f ISO-8859-1 en_US
240localedef -i en_US -f UTF-8 en_US.UTF-8
241localedef -i es_MX -f ISO-8859-1 es_MX
242localedef -i fa_IR -f UTF-8 fa_IR
243localedef -i fr_FR -f ISO-8859-1 fr_FR
244localedef -i fr_FR@euro -f ISO-8859-15 fr_FR@euro
245localedef -i fr_FR -f UTF-8 fr_FR.UTF-8
246localedef -i it_IT -f ISO-8859-1 it_IT
247localedef -i ja_JP -f EUC-JP ja_JP
248localedef -i tr_TR -f UTF-8 tr_TR.UTF-8
249localedef -i zh_CN -f GB18030 zh_CN.GB18030</userinput></screen>
250
251 <para>In addition, install the locale for your own country, language and
252 character set.</para>
253
254 <para>Alternatively, install all locales listed in the
255 <filename>glibc-&glibc-version;/localedata/SUPPORTED</filename> file
256 (it includes every locale listed above and many more) at once with the
257 following time-consuming command:</para>
258
259<screen><userinput remap="locale-full">make localedata/install-locales</userinput></screen>
260
261 <para>Then use the <command>localedef</command> command to create and
262 install locales not listed in the
263 <filename>glibc-&glibc-version;/localedata/SUPPORTED</filename> file
264 in the unlikely case you need them.</para>
265 <!-- The Live CD patches the localedata/SUPPORTED file instead of
266 running localedef, the results are equivalent -->
267
268 </sect2>
269
270 <sect2 id="conf-glibc" role="configuration">
271 <title>Configuring Glibc</title>
272
273 <indexterm zone="conf-glibc">
274 <primary sortas="e-/etc/nsswitch.conf">/etc/nsswitch.conf</primary>
275 </indexterm>
276
277 <indexterm zone="conf-glibc">
278 <primary sortas="e-/etc/localtime">/etc/localtime</primary>
279 </indexterm>
280
281 <para>The <filename>/etc/nsswitch.conf</filename> file needs to be created
282 because, although Glibc provides defaults when this file is missing or corrupt,
283 the Glibc defaults do not work well in a networked environment. The time zone
284 also needs to be configured.</para>
285
286 <para>Create a new file <filename>/etc/nsswitch.conf</filename> by running the
287 following:</para>
288
289<screen><userinput>cat &gt; /etc/nsswitch.conf &lt;&lt; "EOF"
290<literal># Begin /etc/nsswitch.conf
291
292passwd: files
293group: files
294shadow: files
295
296hosts: files dns
297networks: files
298
299protocols: files
300services: files
301ethers: files
302rpc: files
303
304# End /etc/nsswitch.conf</literal>
305EOF</userinput></screen>
306
307 <para>One way to determine the local time zone, run the following
308 script:</para>
309
310<screen role="nodump"><userinput>tzselect</userinput></screen>
311
312 <para>After answering a few questions about the location, the script will
313 output the name of the time zone (e.g.,
314 <emphasis>America/Edmonton</emphasis>). There are also some other possible
315 timezones listed in <filename
316 class='directory'>/usr/share/zoneinfo</filename> such as
317 <emphasis>Canada/Eastern</emphasis> or <emphasis>EST5EDT</emphasis> that
318 are not identified by the script but can be used.</para>
319
320 <para>Then create the <filename>/etc/localtime</filename> file by
321 running:</para>
322
323<screen><userinput>cp -v --remove-destination /usr/share/zoneinfo/<replaceable>&lt;xxx&gt;</replaceable> \
324 /etc/localtime</userinput></screen>
325
326 <para>Replace <replaceable>&lt;xxx&gt;</replaceable> with the name of the
327 time zone selected (e.g., Canada/Eastern).</para>
328
329 <variablelist>
330 <title>The meaning of the cp option:</title>
331
332 <varlistentry>
333 <term><parameter>--remove-destination</parameter></term>
334 <listitem>
335 <para>This is needed to force removal of the already existing symbolic
336 link. The reason for copying the file instead of using a symlink is to
337 cover the situation where <filename class="directory">/usr</filename>
338 is on a separate partition. This could be important when booted into
339 single user mode.</para>
340 </listitem>
341 </varlistentry>
342
343 </variablelist>
344
345 </sect2>
346
347 <sect2 id="conf-ld" role="configuration">
348 <title>Configuring the Dynamic Loader</title>
349
350 <indexterm zone="conf-ld">
351 <primary sortas="e-/etc/ld.so.conf">/etc/ld.so.conf</primary>
352 </indexterm>
353
354 <para>By default, the dynamic loader (<filename
355 class="libraryfile">/lib/ld-linux.so.2</filename>) searches through
356 <filename class="directory">/lib</filename> and <filename
357 class="directory">/usr/lib</filename> for dynamic libraries that are
358 needed by programs as they are run. However, if there are libraries in
359 directories other than <filename class="directory">/lib</filename> and
360 <filename class="directory">/usr/lib</filename>, these need to be added
361 to the <filename>/etc/ld.so.conf</filename> file in order for the
362 dynamic loader to find them. Two directories that are commonly known
363 to contain additional libraries are <filename
364 class="directory">/usr/local/lib</filename> and <filename
365 class="directory">/opt/lib</filename>, so add those directories to the
366 dynamic loader's search path.</para>
367
368 <para>Create a new file <filename>/etc/ld.so.conf</filename> by running the
369 following:</para>
370
371<screen><userinput>cat &gt; /etc/ld.so.conf &lt;&lt; "EOF"
372<literal># Begin /etc/ld.so.conf
373
374/usr/local/lib
375/opt/lib
376
377# End /etc/ld.so.conf</literal>
378EOF</userinput></screen>
379
380 <para>An alternative set up for <filename>/etc/ld.so.conf</filename> allows
381 you to store multiple configuration files in a subdirectory. A new file
382 must then be created for each package that introduces new library paths.
383 Some may find this solution to be more managable, as it does not require
384 you to edit existing files upon either installation or removal of software
385 located in places like <filename class="directory">/opt</filename>. Others
386 may prefer listing all directories in a single file, in which case they
387 should stick to the solution above.</para>
388
389 <para>Create a modular <filename>/etc/ld.so.conf</filename> by running the
390 following:</para>
391
392<screen><userinput>mkdir -v /etc/ld.so.conf.d &amp;&amp;
393cat &gt; /etc/ld.so.conf &lt;&lt; "EOF"
394<literal># Begin /etc/ld.so.conf
395
396include /etc/ld.so.conf.d/*.conf
397
398# End /etc/ld.so.conf</literal>
399EOF</userinput></screen>
400
401 <para>The entries for the directories mentioned earlier should then be
402 placed in a separate file:</para>
403
404<screen><userinput>cat &gt; /etc/ld.so.conf.d/glibc.conf &lt;&lt; "EOF"
405<literal># Begin /etc/ld.so.conf.d/glibc.conf
406
407/usr/local/lib
408/opt/lib
409
410# End /etc/ld.so.conf.d/glibc.conf</literal>
411EOF</userinput></screen>
412
413 </sect2>
414
415 <sect2 id="contents-glibc" role="content">
416 <title>Contents of Glibc</title>
417
418 <segmentedlist>
419 <segtitle>Installed programs</segtitle>
420 <segtitle>Installed libraries</segtitle>
421 <segtitle>Installed directories</segtitle>
422
423 <seglistitem>
424 <seg>catchsegv, gencat, getconf, getent, iconv, iconvconfig, ldconfig,
425 ldd, lddlibc4, locale, localedef, mtrace, nscd, pcprofiledump,
426 pt_chown, rpcgen, rpcinfo, sln, sprof, tzselect, xtrace,
427 zdump, and zic</seg>
428 <seg>ld.so, libBrokenLocale.{a,so}, libSegFault.so, libanl.{a,so},
429 libbsd-compat.a, libc.{a,so}, libc_nonshared.a, libcidn.so,
430 libcrypt.{a,so}, libdl.{a,so}, libg.a, libieee.a, libm.{a,so},
431 libmcheck.a, libmemusage.so, libnsl.{a,so}, libnss_compat.so,
432 libnss_dns.so, libnss_files.so, libnss_hesiod.so, libnss_nis.so,
433 libnss_nisplus.so, libpcprofile.so, libpthread.{a,so},
434 libpthread_nonshared.a, libresolv.{a,so}, librpcsvc.a, librt.{a,so},
435 libthread_db.so, and libutil.{a,so}</seg>
436 <seg>/usr/include/arpa, /usr/include/bits, /usr/include/gnu,
437 /usr/include/net, /usr/include/netash, /usr/include/netatalk,
438 /usr/include/netax25, /usr/include/neteconet, /usr/include/netinet,
439 /usr/include/netipx, /usr/include/netiucv, /usr/include/netpacket,
440 /usr/include/netrom, /usr/include/netrose, /usr/include/nfs,
441 /usr/include/protocols, /usr/include/rpc, /usr/include/rpcsvc,
442 /usr/include/sys, /usr/lib/gconv, /usr/lib/glibc, /usr/lib/locale,
443 /usr/share/i18n, /usr/share/zoneinfo</seg>
444 </seglistitem>
445 </segmentedlist>
446
447 <variablelist>
448 <bridgehead renderas="sect3">Short Descriptions</bridgehead>
449 <?dbfo list-presentation="list"?>
450 <?dbhtml list-presentation="table"?>
451
452 <varlistentry id="catchsegv">
453 <term><command>catchsegv</command></term>
454 <listitem>
455 <para>Can be used to create a stack trace when a program
456 terminates with a segmentation fault</para>
457 <indexterm zone="ch-system-glibc catchsegv">
458 <primary sortas="b-catchsegv">catchsegv</primary>
459 </indexterm>
460 </listitem>
461 </varlistentry>
462
463 <varlistentry id="gencat">
464 <term><command>gencat</command></term>
465 <listitem>
466 <para>Generates message catalogues</para>
467 <indexterm zone="ch-system-glibc gencat">
468 <primary sortas="b-gencat">gencat</primary>
469 </indexterm>
470 </listitem>
471 </varlistentry>
472
473 <varlistentry id="getconf">
474 <term><command>getconf</command></term>
475 <listitem>
476 <para>Displays the system configuration values for file system
477 specific variables</para>
478 <indexterm zone="ch-system-glibc getconf">
479 <primary sortas="b-getconf">getconf</primary>
480 </indexterm>
481 </listitem>
482 </varlistentry>
483
484 <varlistentry id="getent">
485 <term><command>getent</command></term>
486 <listitem>
487 <para>Gets entries from an administrative database</para>
488 <indexterm zone="ch-system-glibc getent">
489 <primary sortas="b-getent">getent</primary>
490 </indexterm>
491 </listitem>
492 </varlistentry>
493
494 <varlistentry id="iconv">
495 <term><command>iconv</command></term>
496 <listitem>
497 <para>Performs character set conversion</para>
498 <indexterm zone="ch-system-glibc iconv">
499 <primary sortas="b-iconv">iconv</primary>
500 </indexterm>
501 </listitem>
502 </varlistentry>
503
504 <varlistentry id="iconvconfig">
505 <term><command>iconvconfig</command></term>
506 <listitem>
507 <para>Creates fastloading <command>iconv</command> module configuration
508 files</para>
509 <indexterm zone="ch-system-glibc iconvconfig">
510 <primary sortas="b-iconvconfig">iconvconfig</primary>
511 </indexterm>
512 </listitem>
513 </varlistentry>
514
515 <varlistentry id="ldconfig">
516 <term><command>ldconfig</command></term>
517 <listitem>
518 <para>Configures the dynamic linker runtime bindings</para>
519 <indexterm zone="ch-system-glibc ldconfig">
520 <primary sortas="b-ldconfig">ldconfig</primary>
521 </indexterm>
522 </listitem>
523 </varlistentry>
524
525 <varlistentry id="ldd">
526 <term><command>ldd</command></term>
527 <listitem>
528 <para>Reports which shared libraries are required
529 by each given program or shared library</para>
530 <indexterm zone="ch-system-glibc ldd">
531 <primary sortas="b-ldd">ldd</primary>
532 </indexterm>
533 </listitem>
534 </varlistentry>
535
536 <varlistentry id="lddlibc4">
537 <term><command>lddlibc4</command></term>
538 <listitem>
539 <para>Assists <command>ldd</command> with object files</para>
540 <indexterm zone="ch-system-glibc lddlibc4">
541 <primary sortas="b-lddlibc4">lddlibc4</primary>
542 </indexterm>
543 </listitem>
544 </varlistentry>
545
546 <varlistentry id="locale">
547 <term><command>locale</command></term>
548 <listitem>
549 <para>Prints various information about the current locale</para>
550 <indexterm zone="ch-system-glibc locale">
551 <primary sortas="b-locale">locale</primary>
552 </indexterm>
553 </listitem>
554 </varlistentry>
555
556 <varlistentry id="localedef">
557 <term><command>localedef</command></term>
558 <listitem>
559 <para>Compiles locale specifications</para>
560 <indexterm zone="ch-system-glibc localedef">
561 <primary sortas="b-localedef">localedef</primary>
562 </indexterm>
563 </listitem>
564 </varlistentry>
565
566 <varlistentry id="mtrace">
567 <term><command>mtrace</command></term>
568 <listitem>
569 <para>Reads and interprets a memory trace file and displays a summary
570 in human-readable format</para>
571 <indexterm zone="ch-system-glibc mtrace">
572 <primary sortas="b-mtrace">mtrace</primary>
573 </indexterm>
574 </listitem>
575 </varlistentry>
576
577 <varlistentry id="nscd">
578 <term><command>nscd</command></term>
579 <listitem>
580 <para>A daemon that provides a cache for the most common name
581 service requests</para>
582 <indexterm zone="ch-system-glibc nscd">
583 <primary sortas="b-nscd">nscd</primary>
584 </indexterm>
585 </listitem>
586 </varlistentry>
587
588 <varlistentry id="pcprofiledump">
589 <term><command>pcprofiledump</command></term>
590 <listitem>
591 <para>Dumps information generated by PC profiling</para>
592 <indexterm zone="ch-system-glibc pcprofiledump">
593 <primary sortas="b-pcprofiledump">pcprofiledump</primary>
594 </indexterm>
595 </listitem>
596 </varlistentry>
597
598 <varlistentry id="pt_chown">
599 <term><command>pt_chown</command></term>
600 <listitem>
601 <para>A helper program for <command>grantpt</command> to set the owner,
602 group and access permissions of a slave pseudo terminal</para>
603 <indexterm zone="ch-system-glibc pt_chown">
604 <primary sortas="b-pt_chown">pt_chown</primary>
605 </indexterm>
606 </listitem>
607 </varlistentry>
608
609 <varlistentry id="rpcgen">
610 <term><command>rpcgen</command></term>
611 <listitem>
612 <para>Generates C code to implement the Remote Procedure Call (RPC)
613 protocol</para>
614 <indexterm zone="ch-system-glibc rpcgen">
615 <primary sortas="b-rpcgen">rpcgen</primary>
616 </indexterm>
617 </listitem>
618 </varlistentry>
619
620 <varlistentry id="rpcinfo">
621 <term><command>rpcinfo</command></term>
622 <listitem>
623 <para>Makes an RPC call to an RPC server</para>
624 <indexterm zone="ch-system-glibc rpcinfo">
625 <primary sortas="b-rpcinfo">rpcinfo</primary>
626 </indexterm>
627 </listitem>
628 </varlistentry>
629
630 <varlistentry id="sln">
631 <term><command>sln</command></term>
632 <listitem>
633 <para>A statically linked <command>ln</command> program</para>
634 <indexterm zone="ch-system-glibc sln">
635 <primary sortas="b-sln">sln</primary>
636 </indexterm>
637 </listitem>
638 </varlistentry>
639
640 <varlistentry id="sprof">
641 <term><command>sprof</command></term>
642 <listitem>
643 <para>Reads and displays shared object profiling data</para>
644 <indexterm zone="ch-system-glibc sprof">
645 <primary sortas="b-sprof">sprof</primary>
646 </indexterm>
647 </listitem>
648 </varlistentry>
649
650 <varlistentry id="tzselect">
651 <term><command>tzselect</command></term>
652 <listitem>
653 <para>Asks the user about the location of the system and reports
654 the corresponding time zone description</para>
655 <indexterm zone="ch-system-glibc tzselect">
656 <primary sortas="b-tzselect">tzselect</primary>
657 </indexterm>
658 </listitem>
659 </varlistentry>
660
661 <varlistentry id="xtrace">
662 <term><command>xtrace</command></term>
663 <listitem>
664 <para>Traces the execution of a program by printing the currently
665 executed function</para>
666 <indexterm zone="ch-system-glibc xtrace">
667 <primary sortas="b-xtrace">xtrace</primary>
668 </indexterm>
669 </listitem>
670 </varlistentry>
671
672 <varlistentry id="zdump">
673 <term><command>zdump</command></term>
674 <listitem>
675 <para>The time zone dumper</para>
676 <indexterm zone="ch-system-glibc zdump">
677 <primary sortas="b-zdump">zdump</primary>
678 </indexterm>
679 </listitem>
680 </varlistentry>
681
682 <varlistentry id="zic">
683 <term><command>zic</command></term>
684 <listitem>
685 <para>The time zone compiler</para>
686 <indexterm zone="ch-system-glibc zic">
687 <primary sortas="b-zic">zic</primary>
688 </indexterm>
689 </listitem>
690 </varlistentry>
691
692 <varlistentry id="ld.so">
693 <term><filename class="libraryfile">ld.so</filename></term>
694 <listitem>
695 <para>The helper program for shared library executables</para>
696 <indexterm zone="ch-system-glibc ld.so">
697 <primary sortas="c-ld.so">ld.so</primary>
698 </indexterm>
699 </listitem>
700 </varlistentry>
701
702 <varlistentry id="libBrokenLocale">
703 <term><filename class="libraryfile">libBrokenLocale</filename></term>
704 <listitem>
705 <para>Used internally by Glibc as a gross hack to get broken programs
706 (e.g., some Motif applications) running. See comments in
707 <filename>glibc-&glibc-version;/locale/broken_cur_max.c</filename>
708 for more information</para>
709 <indexterm zone="ch-system-glibc libBrokenLocale">
710 <primary sortas="c-libBrokenLocale">libBrokenLocale</primary>
711 </indexterm>
712 </listitem>
713 </varlistentry>
714
715 <varlistentry id="libSegFault">
716 <term><filename class="libraryfile">libSegFault</filename></term>
717 <listitem>
718 <para>The segmentation fault signal handler, used by
719 <command>catchsegv</command></para>
720 <indexterm zone="ch-system-glibc libSegFault">
721 <primary sortas="c-libSegFault">libSegFault</primary>
722 </indexterm>
723 </listitem>
724 </varlistentry>
725
726 <varlistentry id="libanl">
727 <term><filename class="libraryfile">libanl</filename></term>
728 <listitem>
729 <para>An asynchronous name lookup library</para>
730 <indexterm zone="ch-system-glibc libanl">
731 <primary sortas="c-libanl">libanl</primary>
732 </indexterm>
733 </listitem>
734 </varlistentry>
735
736 <varlistentry id="libbsd-compat">
737 <term><filename class="libraryfile">libbsd-compat</filename></term>
738 <listitem>
739 <para>Provides the portability needed in order to run certain
740 Berkeley Software Distribution (BSD) programs under Linux</para>
741 <indexterm zone="ch-system-glibc libbsd-compat">
742 <primary sortas="c-libbsd-compat">libbsd-compat</primary>
743 </indexterm>
744 </listitem>
745 </varlistentry>
746
747 <varlistentry id="libc">
748 <term><filename class="libraryfile">libc</filename></term>
749 <listitem>
750 <para>The main C library</para>
751 <indexterm zone="ch-system-glibc libc">
752 <primary sortas="c-libc">libc</primary>
753 </indexterm>
754 </listitem>
755 </varlistentry>
756
757 <varlistentry id="libcidn">
758 <term><filename class="libraryfile">libcidn</filename></term>
759 <listitem>
760 <para>Used internally by Glibc for handling internationalized domain
761 names in the <function>getaddrinfo()</function> function</para>
762 <indexterm zone="ch-system-glibc libcidn">
763 <primary sortas="c-libcidn">libcidn</primary>
764 </indexterm>
765 </listitem>
766 </varlistentry>
767
768 <varlistentry id="libcrypt">
769 <term><filename class="libraryfile">libcrypt</filename></term>
770 <listitem>
771 <para>The cryptography library</para>
772 <indexterm zone="ch-system-glibc libcrypt">
773 <primary sortas="c-libcrypt">libcrypt</primary>
774 </indexterm>
775 </listitem>
776 </varlistentry>
777
778 <varlistentry id="libdl">
779 <term><filename class="libraryfile">libdl</filename></term>
780 <listitem>
781 <para>The dynamic linking interface library</para>
782 <indexterm zone="ch-system-glibc libdl">
783 <primary sortas="c-libdl">libdl</primary>
784 </indexterm>
785 </listitem>
786 </varlistentry>
787
788 <varlistentry id="libg">
789 <term><filename class="libraryfile">libg</filename></term>
790 <listitem>
791 <para>Dummy library containing no functions. Previously was a runtime
792 library for <command>g++</command></para>
793 <indexterm zone="ch-system-glibc libg">
794 <primary sortas="c-libg">libg</primary>
795 </indexterm>
796 </listitem>
797 </varlistentry>
798
799 <varlistentry id="libieee">
800 <term><filename class="libraryfile">libieee</filename></term>
801 <listitem>
802 <para>Linking in this module forces error handling rules for math
803 functions as defined by the Institute of Electrical and Electronic
804 Engineers (IEEE). The default is POSIX.1 error handling</para>
805 <indexterm zone="ch-system-glibc libieee">
806 <primary sortas="c-libieee">libieee</primary>
807 </indexterm>
808 </listitem>
809 </varlistentry>
810
811 <varlistentry id="libm">
812 <term><filename class="libraryfile">libm</filename></term>
813 <listitem>
814 <para>The mathematical library</para>
815 <indexterm zone="ch-system-glibc libm">
816 <primary sortas="c-libm">libm</primary>
817 </indexterm>
818 </listitem>
819 </varlistentry>
820
821 <varlistentry id="libmcheck">
822 <term><filename class="libraryfile">libmcheck</filename></term>
823 <listitem>
824 <para>Turns on memory allocation checking when linked to</para>
825 <indexterm zone="ch-system-glibc libmcheck">
826 <primary sortas="c-libmcheck">libmcheck</primary>
827 </indexterm>
828 </listitem>
829 </varlistentry>
830
831 <varlistentry id="libmemusage">
832 <term><filename class="libraryfile">libmemusage</filename></term>
833 <listitem>
834 <para>Used by <command>memusage</command> to help collect
835 information about the memory usage of a program</para>
836 <indexterm zone="ch-system-glibc libmemusage">
837 <primary sortas="c-libmemusage">libmemusage</primary>
838 </indexterm>
839 </listitem>
840 </varlistentry>
841
842 <varlistentry id="libnsl">
843 <term><filename class="libraryfile">libnsl</filename></term>
844 <listitem>
845 <para>The network services library</para>
846 <indexterm zone="ch-system-glibc libnsl">
847 <primary sortas="c-libnsl">libnsl</primary>
848 </indexterm>
849 </listitem>
850 </varlistentry>
851
852 <varlistentry id="libnss">
853 <term><filename class="libraryfile">libnss</filename></term>
854 <listitem>
855 <para>The Name Service Switch libraries, containing functions for
856 resolving host names, user names, group names, aliases, services,
857 protocols, etc.</para>
858 <indexterm zone="ch-system-glibc libnss">
859 <primary sortas="c-libnss">libnss</primary>
860 </indexterm>
861 </listitem>
862 </varlistentry>
863
864 <varlistentry id="libpcprofile">
865 <term><filename class="libraryfile">libpcprofile</filename></term>
866 <listitem>
867 <para>Contains profiling functions used to track the amount of CPU
868 time spent in specific source code lines</para>
869 <indexterm zone="ch-system-glibc libpcprofile">
870 <primary sortas="c-libpcprofile">libpcprofile</primary>
871 </indexterm>
872 </listitem>
873 </varlistentry>
874
875 <varlistentry id="libpthread">
876 <term><filename class="libraryfile">libpthread</filename></term>
877 <listitem>
878 <para>The POSIX threads library</para>
879 <indexterm zone="ch-system-glibc libpthread">
880 <primary sortas="c-libpthread">libpthread</primary>
881 </indexterm>
882 </listitem>
883 </varlistentry>
884
885 <varlistentry id="libresolv">
886 <term><filename class="libraryfile">libresolv</filename></term>
887 <listitem>
888 <para>Contains functions for creating, sending, and interpreting
889 packets to the Internet domain name servers</para>
890 <indexterm zone="ch-system-glibc libresolv">
891 <primary sortas="c-libresolv">libresolv</primary>
892 </indexterm>
893 </listitem>
894 </varlistentry>
895
896 <varlistentry id="librpcsvc">
897 <term><filename class="libraryfile">librpcsvc</filename></term>
898 <listitem>
899 <para>Contains functions providing miscellaneous RPC services</para>
900 <indexterm zone="ch-system-glibc librpcsvc">
901 <primary sortas="c-librpcsvc">librpcsvc</primary>
902 </indexterm>
903 </listitem>
904 </varlistentry>
905
906 <varlistentry id="librt">
907 <term><filename class="libraryfile">librt</filename></term>
908 <listitem>
909 <para>Contains functions providing most of the interfaces specified
910 by the POSIX.1b Realtime Extension</para>
911 <indexterm zone="ch-system-glibc librt">
912 <primary sortas="c-librt">librt</primary>
913 </indexterm>
914 </listitem>
915 </varlistentry>
916
917 <varlistentry id="libthread_db">
918 <term><filename class="libraryfile">libthread_db</filename></term>
919 <listitem>
920 <para>Contains functions useful for building debuggers for
921 multi-threaded programs</para>
922 <indexterm zone="ch-system-glibc libthread_db">
923 <primary sortas="c-libthread_db">libthread_db</primary>
924 </indexterm>
925 </listitem>
926 </varlistentry>
927
928 <varlistentry id="libutil">
929 <term><filename class="libraryfile">libutil</filename></term>
930 <listitem>
931 <para>Contains code for <quote>standard</quote> functions used in
932 many different Unix utilities</para>
933 <indexterm zone="ch-system-glibc libutil">
934 <primary sortas="c-libutil">libutil</primary>
935 </indexterm>
936 </listitem>
937 </varlistentry>
938
939 </variablelist>
940
941 </sect2>
942
943</sect1>