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nan(3p) [posix man page]

NAN(3P) 						     POSIX Programmer's Manual							   NAN(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
nan, nanf, nanl -- return quiet NaN SYNOPSIS
#include <math.h> double nan(const char *tagp); float nanf(const char *tagp); long double nanl(const char *tagp); 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. The function call nan("n-char-sequence") shall be equivalent to: strtod("NAN(n-char-sequence)", (char **) NULL); The function call nan("") shall be equivalent to: strtod("NAN()", (char **) NULL) If tagp does not point to an n-char sequence or an empty string, the function call shall be equivalent to: strtod("NAN", (char **) NULL) Function calls to nanf() and nanl() are equivalent to the corresponding function calls to strtof() and strtold(). RETURN VALUE
These functions shall return a quiet NaN, if available, with content indicated through tagp. If the implementation does not support quiet NaNs, these functions shall return zero. ERRORS
No errors are defined. The following sections are informative. EXAMPLES
None. APPLICATION USAGE
None. RATIONALE
None. FUTURE DIRECTIONS
None. SEE ALSO
strtod() 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 NAN(3P)

Check Out this Related Man Page

NAN(3P) 						     POSIX Programmer's Manual							   NAN(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
nan, nanf, nanl - return quiet NaN SYNOPSIS
#include <math.h> double nan(const char *tagp); float nanf(const char *tagp); long double nanl(const char *tagp); DESCRIPTION
The function call nan("n-char-sequence") shall be equivalent to: strtod("NAN(n-char-sequence)", (char **) NULL); The function call nan("") shall be equivalent to: strtod("NAN()", (char **) NULL) If tagp does not point to an n- char sequence or an empty string, the function call shall be equivalent to: strtod("NAN", (char **) NULL) Function calls to nanf() and nanl() are equivalent to the corresponding function calls to strtof() and strtold(). RETURN VALUE
These functions shall return a quiet NaN, if available, with content indicated through tagp. If the implementation does not support quiet NaNs, these functions shall return zero. ERRORS
No errors are defined. The following sections are informative. EXAMPLES
None. APPLICATION USAGE
None. RATIONALE
None. FUTURE DIRECTIONS
None. SEE ALSO
strtod(), strtold(), the Base Definitions volume of IEEE Std 1003.1-2001, <math.h> COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol- ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. 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 Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . IEEE
/The Open Group 2003 NAN(3P)

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