nan (3p) - Linux Man Pages
nan: return quiet NaN
PROLOGThis manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.
nan, nanf, nanl - return quiet NaN
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)
These functions shall return a quiet NaN, if available, with content indicated through tagp.
No errors are defined.
COPYRIGHTPortions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology -- 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 .