1 .\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk)
3 .\" %%%LICENSE_START(VERBATIM)
4 .\" Permission is granted to make and distribute verbatim copies of this
5 .\" manual provided the copyright notice and this permission notice are
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8 .\" Permission is granted to copy and distribute modified versions of this
9 .\" manual under the conditions for verbatim copying, provided that the
10 .\" entire resulting derived work is distributed under the terms of a
11 .\" permission notice identical to this one.
13 .\" Since the Linux kernel and libraries are constantly changing, this
14 .\" manual page may be incorrect or out-of-date. The author(s) assume no
15 .\" responsibility for errors or omissions, or for damages resulting from
16 .\" the use of the information contained herein. The author(s) may not
17 .\" have taken the same level of care in the production of this manual,
18 .\" which is licensed free of charge, as they might when working
21 .\" Formatted or processed versions of this manual, if unaccompanied by
22 .\" the source, must acknowledge the copyright and authors of this work.
25 .\" References consulted:
26 .\" Linux libc source code
27 .\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991)
29 .\" Modified Mon Mar 29 22:31:13 1993, David Metcalfe
30 .\" Modified Sun Jun 6 23:27:50 1993, David Metcalfe
31 .\" Modified Sat Jul 24 21:45:37 1993, Rik Faith (faith@cs.unc.edu)
32 .\" Modified Sat Dec 16 15:02:59 2000, Joseph S. Myers
34 .TH ABS 3 2016-03-15 "GNU" "Linux Programmer's Manual"
36 abs, labs, llabs, imaxabs \- compute the absolute value of an integer
39 .B #include <stdlib.h>
41 .BI "int abs(int " j );
42 .BI "long int labs(long int " j );
43 .BI "long long int llabs(long long int " j );
45 .B #include <inttypes.h>
47 .BI "intmax_t imaxabs(intmax_t " j );
51 Feature Test Macro Requirements for glibc (see
52 .BR feature_test_macros (7)):
58 _ISOC99_SOURCE || _POSIX_C_SOURCE\ >=\ 200112L
64 function computes the absolute value of the integer
71 functions compute the absolute value of the argument \fIj\fP of the
72 appropriate integer type for the function.
74 Returns the absolute value of the integer argument, of the appropriate
75 integer type for the function.
77 For an explanation of the terms used in this section, see
84 Interface Attribute Value
90 T} Thread safety MT-Safe
94 POSIX.1-2001, POSIX.1-2008, C99, SVr4, 4.3BSD.
95 .\" POSIX.1 (1996 edition) requires only the
103 functions; the functions
109 Trying to take the absolute value of the most negative integer
114 function is included in glibc since version 2.0.
117 function is included in
118 glibc since version 2.1.1.
122 to be declared, it may be necessary to define
123 \fB_ISOC99_SOURCE\fP or \fB_ISOC9X_SOURCE\fP (depending on the
124 version of glibc) before including any standard headers.
134 as built-in functions.