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68 lines
1.8 KiB
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68 lines
1.8 KiB
Plaintext
.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved
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.TH "ATOF" P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual"
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.\" atof
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.SH NAME
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atof \- convert a string to a double-precision number
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.SH SYNOPSIS
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.LP
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\fB#include <stdlib.h>
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.br
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.sp
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double atof(const char *\fP\fIstr\fP\fB);
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.br
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\fP
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.SH DESCRIPTION
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.LP
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The call \fIatof\fP(\fIstr\fP) shall be equivalent to:
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.sp
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.RS
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.nf
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\fBstrtod(\fP\fIstr\fP\fB,(char **)NULL),
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\fP
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.fi
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.RE
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.LP
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except that the handling of errors may differ. If the value cannot
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be represented, the behavior is undefined.
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.SH RETURN VALUE
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.LP
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The \fIatof\fP() function shall return the converted value if the
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value can be represented.
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.SH ERRORS
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.LP
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No errors are defined.
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.LP
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\fIThe following sections are informative.\fP
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.SH EXAMPLES
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.LP
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None.
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.SH APPLICATION USAGE
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.LP
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The \fIatof\fP() function is subsumed by \fIstrtod\fP() but is retained
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because it is
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used extensively in existing code. If the number is not known to be
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in range, \fIstrtod\fP() should be used because \fIatof\fP() is not
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required to perform any error
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checking.
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.SH RATIONALE
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.LP
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None.
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.SH FUTURE DIRECTIONS
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.LP
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None.
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.SH SEE ALSO
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.LP
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\fIstrtod\fP() , the Base Definitions volume of IEEE\ Std\ 1003.1-2001,
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\fI<stdlib.h>\fP
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.SH COPYRIGHT
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Portions of this text are reprinted and reproduced in electronic form
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from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
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-- Portable Operating System Interface (POSIX), The Open Group Base
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Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
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Electrical and Electronics Engineers, Inc and The Open Group. In the
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event of any discrepancy between this version and the original IEEE and
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The Open Group Standard, the original IEEE and The Open Group Standard
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is the referee document. The original Standard can be obtained online at
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http://www.opengroup.org/unix/online.html .
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