The Regents of the University of California. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
3. All advertising materials mentioning features or use of this software
must display the following acknowledgement:
This product includes software developed by the University of
California, Berkeley and its contributors.
4. Neither the name of the University nor the names of its contributors
may be used to endorse or promote products derived from this software
without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
@(#)intro.3 8.2 (Berkeley) 4/28/95
.Dd April 28, 1995 .Dt INTRO 3 .Os BSD 4 .Sh NAME .Nm intro .Nd introduction to the C libraries .Sh DESCRIPTION This section provides an overview of the C library functions, their error returns and other common definitions and concepts. Most of these functions are available from the C library, .Em libc . Other libraries, such as the math library, .Em libm , must be indicated at compile time with the .Fl l option of the compiler.
p A subset of the .Xr libc functions are available from Fortran; they are described separately in .Xr intro 3f .
p The various libraries (followed by the loader flag): l -tag -width "libc (-lc)" t Xr libc Pq Fl l Ns Ar c Standard C library functions. When using the C compiler .Xr cc 1 , it is not necessary to supply the loader flag .Fl l Ns Ar c for these functions. There are several `libraries' or groups of functions included inside of .Xr libc : the standard .Tn I/O routines, database routines, bit operators, string operators, character tests and character operators, des encryption routines, storage allocation, time functions, signal handling and more. t Xo .Xr libcurses
f ( Fl l Ns Ar curses
.Fl l Ns Ar termcap )
.Xc
Terminal independent screen management routines
for two dimensional non-bitmap display terminals.
(See
.Xr curses 3 . )
t Xr libcompat Pq Fl l Ns Ar compat Functions which are obsolete but are available for compatibility with
x 4.3 . In particular,
a number of system call interfaces provided in previous releases of
x have been included for source code compatibility.
Use of these routines should, for the most part, be avoided.
The manual page entry for each compatibility routine
indicates the proper interface to use.
.It Xr libkvm
t Xr libl Pq Fl l Ns Ar l The library for
.Xr lex 1 .
.It Xr libln
t Xr libm Pq Fl l Ns Ar m The math library,
.Em libm .
The math library is loaded as needed by the Pascal compiler
.Xr pc 1 ,
but not by the C compiler which requires the
.Fl l Ns Ar m
flag.
(See
.Xr math 3 . )
t Xr libmp Pq Fl l Ns Ar mp .It Xr libom
Old math library.
t Xr libplot Pq Fl l Ns Ar plot Device independent plotting functions.
(See
.Xr plot 3 . )
t Xr libplotf77 Pq Fl l Ns Ar plotf77 The device independent plotting functions for fortran.
(See
.Xr plot 3 . )
.It Xr libresolv Pq Fl l Ns Ar resolv
Routines for network address resolution.
t Xr libtermcap Fl l Ns Ar termcap The terminal independent operation library package. (See
.Xr termcap 3 . )
.It libvt0.a
t Xr liby Pq Fl l Ns Ar y The library for
.Xr yacc 1 .
.El
.Sh FILES
l -tag -width /usr/lib/libm_p.a -compact t Pa /usr/lib/libc.a the C library
t Pa /usr/lib/libm.a the math library
t Pa /usr/lib/libc_p.a the C library compiled for profiling
t Pa /usr/lib/libm_p.a the math library compiled for profiling
.El
.Sh SEE ALSO
.Xr libc 3 ,
.Xr stdio 3 ,
.Xr math 3 ,
.Xr intro 2 ,
.Xr cc 1 ,
.Xr ld 1 ,
.Xr nm 1
.Sh LIST OF FUNCTIONS
.Bl -column "strncasecmpxxx" "system"
.Sy Name Description
.El
.Sh HISTORY
An
.Nm intro
manual appeared in
.At v7 .
Indexes created Tue Sep 30 20:09:53 GMT 2025