1INTRO(3) Linux Programmer's Manual INTRO(3)
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6 intro - introduction to library functions
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9 Section 3 of the manual describes all library functions excluding the
10 library functions (system call wrappers) described in Section 2, which
11 implement system calls.
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13 Many of the functions described in the section are part of the Standard
14 C Library (libc). Some functions are part of other libraries (e.g.,
15 the math library, libm, or the real-time library, librt) in which case
16 the manual page will indicate the linker option needed to link against
17 the required library (e.g., -lm and -lrt, respectively, for the afore‐
18 mentioned libraries).
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20 In some cases, the programmer must define a feature test macro in order
21 to obtain the declaration of a function from the header file specified
22 in the man page SYNOPSIS section. (Where required, these feature test
23 macros must be defined before including any header files.) In such
24 cases, the required macro is described in the man page. For further
25 information on feature test macros, see feature_test_macros(7).
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28 Certain terms and abbreviations are used to indicate UNIX variants and
29 standards to which calls in this section conform. See standards(7).
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32 Authors and copyright conditions
33 Look at the header of the manual page source for the author(s) and
34 copyright conditions. Note that these can be different from page to
35 page!
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38 intro(2), errno(3), capabilities(7), credentials(7), environ(7), fea‐
39 ture_test_macros(7), libc(7), math_error(7), path_resolution(7),
40 pthreads(7), signal(7), standards(7), system_data_types(7)
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43 This page is part of release 5.12 of the Linux man-pages project. A
44 description of the project, information about reporting bugs, and the
45 latest version of this page, can be found at
46 https://www.kernel.org/doc/man-pages/.
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50Linux 2020-11-01 INTRO(3)