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55 lines
1.2 KiB
Groff
55 lines
1.2 KiB
Groff
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.TH FMTSTRTOD 3
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.SH NAME
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fmtstrtod, fmtcharstod \ - convert text to numbers
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.SH SYNOPSIS
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.B #include <utf.h>
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.br
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.B #include <fmt.h>
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.PP
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.PP
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.B
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double fmtstrtod(char *nptr, char **rptr)
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.PP
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.B
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double fmtcharstod(int (*f)(void *), void *a)
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.SH DESCRIPTION
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.I Fmtstrtod
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converts a string pointed to by
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.I nptr
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to floating point representation and, if
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.I rptr
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is not zero, sets
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.I *rptr
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to point to the input character immediately after the string converted.
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.I Fmtstrtod
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recognizes an optional string of tabs and spaces,
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then an optional sign, then a string of digits optionally
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containing a decimal point, then an optional
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.L e
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or
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.L E
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followed by an optionally signed integer.
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.PP
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.PP
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.I Fmtcharstod
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interprets floating point numbers in the manner of
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.IR atof ,
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but gets successive characters by calling
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.BR (*\fIf\fP)(a) .
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The last call to
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.I f
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terminates the scan, so it must have returned a character that
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is not a legal continuation of a number.
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Therefore, it may be necessary to back up the input stream one character
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after calling
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.IR fmtcharstod .
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.SH SOURCE
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.B http://swtch.com/plan9port/unix
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.SH SEE ALSO
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.IR fscanf (3)
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.SH DIAGNOSTICS
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Zero is returned if the beginning of the input string is not interpretable
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as a number; even in this case,
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.I rptr
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will be updated.
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