posix man page for trunc

TRUNC(3P)						     POSIX Programmer's Manual							 TRUNC(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       trunc, truncf, truncl -- round to truncated integer value

SYNOPSIS
       #include <math.h>

       double trunc(double x);
       float truncf(float x);
       long double truncl(long double x);

DESCRIPTION
       The functionality described on this reference page is aligned with the ISO C standard. Any conflict between the requirements described here
       and the ISO C standard is unintentional. This volume of POSIX.1-2008 defers to the ISO C standard.

       These  functions  shall round their argument to the integer value, in floating format, nearest to but no larger in magnitude than the argu-
       ment.

RETURN VALUE
       Upon successful completion, these functions shall return the truncated integer value.
       The result shall have the same sign as x.

       If x is NaN, a NaN shall be returned.

       If x is +-0 or +-Inf, x shall be returned.

ERRORS
       No errors are defined.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       The integral value returned by these functions need not be expressible as an intmax_t.  The return value should be tested before  assigning
       it to an integer type to avoid the undefined results of an integer overflow.

       These functions may raise the inexact floating-point exception if the result differs in value from the argument.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       The Base Definitions volume of POSIX.1-2008, <math.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2013 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, Copyright (C)  2013  by	the  Institute	of
       Electrical and Electronics Engineers, Inc and The Open Group.  (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) In the
       event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Stan-
       dard is the referee document. The original Standard can be obtained online at http://www.unix.org/online.html .

       Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source
       files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE
/The Open Group						       2013								 TRUNC(3P)