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Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)intro.3 8.1 (Berkeley) 6/5/93 29.\" $FreeBSD$ 30.\" 31.Dd November 7, 2022 32.Dt INTRO 3 33.Os 34.Sh NAME 35.Nm intro 36.Nd introduction to the C libraries 37.Sh SYNOPSIS 38.Nm cc 39.Op Ar flags 40.Ar 41.Op Fl llibrary 42.Sh DESCRIPTION 43This section provides an overview of the C 44library functions, their error returns and other 45common definitions and concepts. 46Most of these functions are available from the C library, 47.Em libc . 48Other libraries, such as the math library, 49.Em libm , 50must be indicated at compile time with the 51.Fl l 52option of the compiler. 53.Pp 54The various libraries (followed by the loader flag): 55.Bl -tag -width "libbluetooth" 56.It Em libbluetooth 57.Pq Fl l Ns Ar bluetooth 58The bluetooth library. 59See 60.Xr bluetooth 3 . 61.It Em libc 62.Pq Fl l Ns Ar c 63Standard C library functions. 64When using the C compiler 65.Xr cc 1 , 66it is not necessary 67to supply the loader flag 68.Fl l Ns Ar c 69for these functions. 70There are several `libraries' or groups of functions included inside of 71.Em libc : 72.Bl -tag -width "XXXXXX" 73.It standard I/O routines 74see 75.Xr stdio 3 76.It database routines 77see 78.Xr db 3 79.It bit operators 80see 81.Xr bitstring 3 82.It string operators 83see 84.Xr string 3 85.It character tests and character operators 86.It storage allocation 87see 88.Xr mpool 3 89.It regular-expressions 90see 91.Xr regex 3 92.It remote procedure calls (RPC) 93see 94.Xr rpc 3 95.It time functions 96see 97.Xr time 3 98.It signal handling 99see 100.Xr signal 3 101.El 102.It Em libcalendar 103.Pq Fl l Ns Ar calendar 104The calendar arithmetic library. 105See 106.Xr calendar 3 . 107.It Em libcam 108.Pq Fl l Ns Ar cam 109The common access method user library. 110See 111.Xr cam 3 . 112.It Em libcrypt 113.Pq Fl l Ns Ar crypt 114The crypt library. 115See 116.Xr crypt 3 . 117.It Em libcurses 118.Pq Fl l Ns Ar curses Fl l Ns Ar termcap 119Terminal independent screen management routines 120for two dimensional non-bitmap display terminals. 121See 122.Xr ncurses 3 . 123.It Em libcuse 124.Pq Fl l Ns Ar cuse 125The userland character device library. 126See 127.Xr cuse 3 . 128.It Em libcompat 129.Pq Fl l Ns Ar compat 130Functions which are obsolete but are available for compatibility with 131.Bx 4.3 . 132In particular, 133a number of system call interfaces provided in previous releases of 134.Bx 135have been included for source code compatibility. 136Use of these routines should, for the most part, be avoided. 137The manual page entry for each compatibility routine 138indicates the proper interface to use. 139.It Em libdevinfo 140.Pq Fl l Ns Ar devinfo 141The Device and Resource Information Utility library. 142See 143.Xr devinfo 3 . 144.It Em libdevstat 145.Pq Fl l Ns Ar devstat 146The Device Statistics library. 147See 148.Xr devstat 3 . 149.It Em libdwarf 150.Pq Fl l Ns Ar dwarf 151The DWARF access library. 152See 153.Xr dwarf 3 . 154.It Em libelf 155.Pq Fl l Ns Ar elf 156The ELF access library. 157See 158.Xr elf 3 . 159.It Em libfetch 160.Pq Fl l Ns Ar fetch 161The file transfer library. 162See 163.Xr fetch 3 . 164.It Em libfigpar 165.Pq Fl l Ns Ar figpar 166The configuration file parsing library. 167See 168.Xr figpar 3 . 169.It Em libgpio 170.Pq Fl l Ns Ar gpio 171The general-purpose input output library (GPIO). 172See 173.Xr gpio 3 . 174.It Em libgssapi 175.Pq Fl l Ns Ar gssapi 176The generic security service application programming 177interface. 178See 179.Xr gssapi 3 . 180.It Em libjail 181.Pq Fl l Ns Ar jail 182The jail library. 183See 184.Xr jail 3 . 185.It Em libkvm 186.Pq Fl l Ns Ar kvm 187Functions used to access kernel memory are in this library. 188They can be used 189against both a running system and a crash dump. 190See 191.Xr kvm 3 . 192.It Em libl 193.Pq Fl l Ns Ar l 194The library for 195.Xr lex 1 . 196.It Em libm 197.Pq Fl l Ns Ar m 198The math library. 199See 200.Xr math 3 . 201.It Em libmd 202.Pq Fl l Ns Ar md 203The message digest library. 204See 205.Xr md4 3 , 206.Xr md5 3 , 207.Xr sha 3 , 208.Xr sha256 3 , 209.Xr sha512 3 , 210.Xr ripemd 3 , 211.Xr skein 3 . 212.It Em libmp 213.Pq Fl l Ns Ar mp 214.It Em libpam 215.Pq Fl l Ns Ar pam 216The pluggable authentication module library. 217See 218.Xr pam 3 . 219.It Em libpcap 220.Pq Fl l Ns Ar pcap 221The packet capture library. 222See 223.Xr pcap 3 . 224.It Em libpmc 225.Pq Fl l Ns Ar pmc 226The performance counters library. 227See 228.Xr pmc 3 . 229.It Em libpthread 230.Pq Fl l Ns Ar pthread 231The POSIX threads library. 232See 233.Xr pthread 3 . 234.It Em libstdthreads 235.Pq Fl l Ns Ar stdthreads 236The ISO C11 standard 237.In threads.h 238library. 239See 240.Xr thrd_create 3 . 241.It Em libsysdecode 242.Pq Fl l Ns Ar sysdecode 243The system argument decoding library. 244See 245.Xr sysdecode 3 . 246.It Em libtermcap 247.Pq Fl l Ns Ar termcap 248The terminal independent operation library package. 249See 250.Xr termcap 3 . 251.It Em libusb 252.Pq Fl l Ns Ar usb 253The USB access library. 254See 255.Xr usb 3 . 256.It Em libvgl 257.Pq Fl l Ns Ar vgl 258The video graphics library. 259See 260.Xr vgl 3 . 261.It Em liby 262.Pq Fl l Ns Ar y 263The library for 264.Xr yacc 1 . 265.It Em libz 266.Pq Fl l Ns Ar z 267The general-purpose data compression library. 268See 269.Xr zlib 3 . 270.El 271.Sh FILES 272.Bl -tag -width /usr/lib/libm_p.a -compact 273.It Pa /usr/lib/libc.a 274the C library 275.It Pa /usr/lib/libc_p.a 276the C library compiled for profiling 277.It Pa /usr/lib/libm.a 278the math library 279.It Pa /usr/lib/libm_p.a 280the math library compiled for profiling 281.El 282.Sh SEE ALSO 283.Xr cc 1 , 284.Xr ld 1 , 285.Xr nm 1 , 286.Xr intro 2 , 287.Xr math 3 , 288.Xr stdio 3 289.Sh HISTORY 290An 291.Nm 292manual appeared in 293.At v7 . 294