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diff --git a/man3/abs.3 b/man3/abs.3 new file mode 100644 index 0000000..1d70ba5 --- /dev/null +++ b/man3/abs.3 @@ -0,0 +1,125 @@ +'\" t +.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) +.\" +.\" SPDX-License-Identifier: Linux-man-pages-copyleft +.\" +.\" References consulted: +.\" Linux libc source code +.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) +.\" 386BSD man pages +.\" Modified Mon Mar 29 22:31:13 1993, David Metcalfe +.\" Modified Sun Jun 6 23:27:50 1993, David Metcalfe +.\" Modified Sat Jul 24 21:45:37 1993, Rik Faith (faith@cs.unc.edu) +.\" Modified Sat Dec 16 15:02:59 2000, Joseph S. Myers +.\" +.TH abs 3 2023-07-20 "Linux man-pages 6.05.01" +.SH NAME +abs, labs, llabs, imaxabs \- compute the absolute value of an integer +.SH LIBRARY +Standard C library +.RI ( libc ", " \-lc ) +.SH SYNOPSIS +.nf +.B #include <stdlib.h> +.PP +.BI "int abs(int " j ); +.BI "long labs(long " j ); +.BI "long long llabs(long long " j ); +.PP +.B #include <inttypes.h> +.PP +.BI "intmax_t imaxabs(intmax_t " j ); +.fi +.PP +.RS -4 +Feature Test Macro Requirements for glibc (see +.BR feature_test_macros (7)): +.RE +.PP +.BR llabs (): +.nf + _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L +.fi +.SH DESCRIPTION +The +.BR abs () +function computes the absolute value of the integer +argument \fIj\fP. +The +.BR labs (), +.BR llabs (), +and +.BR imaxabs () +functions compute the absolute value of the argument \fIj\fP of the +appropriate integer type for the function. +.SH RETURN VALUE +Returns the absolute value of the integer argument, of the appropriate +integer type for the function. +.SH ATTRIBUTES +For an explanation of the terms used in this section, see +.BR attributes (7). +.TS +allbox; +lbx lb lb +l l l. +Interface Attribute Value +T{ +.na +.nh +.BR abs (), +.BR labs (), +.BR llabs (), +.BR imaxabs () +T} Thread safety MT-Safe +.TE +.sp 1 +.SH STANDARDS +C11, POSIX.1-2008. +.SH HISTORY +POSIX.1-2001, C99, SVr4, 4.3BSD. +.\" POSIX.1 (1996 edition) requires only the +.\" .BR abs () +.\" function. +.PP +C89 only +includes the +.BR abs () +and +.BR labs () +functions; the functions +.BR llabs () +and +.BR imaxabs () +were added in C99. +.SH NOTES +Trying to take the absolute value of the most negative integer +is not defined. +.PP +The +.BR llabs () +function is included since glibc 2.0. +The +.BR imaxabs () +function is included since glibc 2.1.1. +.PP +For +.BR llabs () +to be declared, it may be necessary to define +\fB_ISOC99_SOURCE\fP or \fB_ISOC9X_SOURCE\fP (depending on the +version of glibc) before including any standard headers. +.PP +By default, +GCC handles +.BR abs (), +.BR labs (), +and (since GCC 3.0) +.BR llabs () +and +.BR imaxabs () +as built-in functions. +.SH SEE ALSO +.BR cabs (3), +.BR ceil (3), +.BR fabs (3), +.BR floor (3), +.BR rint (3) |