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'\"
'\" Copyright (c) 1989-1993 The Regents of the University of California.
'\" Copyright (c) 1994-1997 Sun Microsystems, Inc.
'\"
'\" See the file "license.terms" for information on usage and redistribution
'\" of this file, and for a DISCLAIMER OF ALL WARRANTIES.
'\" 
'\" SCCS: @(#) PrintDbl.3 1.9 97/08/22 13:30:22
'\" 
.so man.macros
.TH Tcl_PrintDouble 3 8.0 Tcl "Tcl Library Procedures"
.BS
.SH NAME
Tcl_PrintDouble \- Convert floating value to string
.SH SYNOPSIS
.nf
\fB#include <tcl.h>\fR
.sp
\fBTcl_PrintDouble\fR(\fIinterp, value, dst\fR)
.SH ARGUMENTS
.AS Tcl_Interp *interp
.AP Tcl_Interp *interp in
.VS
Before Tcl 8.0, the \fBtcl_precision\fR variable in this interpreter
controlled the conversion.  As of Tcl 8.0, this argument is ignored and
the conversion is controlled by the \fBtcl_precision\fR variable
that is now shared by all interpreters.
.VE
.AP double value in
Floating-point value to be converted.
.AP char *dst out
Where to store string representing \fIvalue\fR.  Must have at
least TCL_DOUBLE_SPACE characters of storage.
.BE

.SH DESCRIPTION
.PP
\fBTcl_PrintDouble\fR generates a string that represents the value
of \fIvalue\fR and stores it in memory at the location given by
\fIdst\fR.  It uses \fB%g\fR format to generate the string, with one
special twist: the string is guaranteed to contain either
a ``.'' or an ``e'' so that it doesn't look like an integer.  Where
\fB%g\fR would generate an integer with no decimal point, \fBTcl_PrintDouble\fR
adds ``.0''.

.SH KEYWORDS
conversion, double-precision, floating-point, string