tcl7.6 C API - GetInt






NAME

     Tcl_GetInt, Tcl_GetDouble,  Tcl_GetBoolean  -  convert  from
     string to integer, double, or boolean


SYNOPSIS

     #include <tcl.h>

     int
     Tcl_GetInt(interp, string, intPtr)

     int
     Tcl_GetDouble(interp, string, doublePtr)

     int
     Tcl_GetBoolean(interp, string, boolPtr)


ARGUMENTS

     Tcl_Interp   *interp      (in)      Interpreter to  use  for
                                         error reporting.

     char         *string      (in)      Textual value to be con-
                                         verted.

     int          *intPtr      (out)     Points to place to store
                                         integer  value converted
                                         from string.

     double       *doublePtr   (out)     Points to place to store
                                         double-precision
                                         floating-point     value
                                         converted from string.

     int          *boolPtr     (out)     Points to place to store
                                         boolean  value  (0 or 1)
                                         converted from string.





DESCRIPTION

     These  procedures  convert  from  strings  to  integers   or
     double-precision    floating-point    values   or   booleans
     (represented as 0- or 1-valued integers).  Each of the  pro-
     cedures  takes a string argument, converts it to an internal
     form of a particular type, and stores the converted value at
     the  location  indicated  by the procedure's third argument.
     If all goes well, each of the procedures returns TCL_OK.  If
     string  doesn't  have the proper syntax for the desired type
     then TCL_ERROR is returned, an  error  message  is  left  in
     interp->result,  and  nothing is stored at *intPtr or *doub-
     lePtr or *boolPtr.
     Tcl_GetInt expects string to  consist  of  a  collection  of
     integer digits, optionally signed and optionally preceded by
     white space.  If the first  two  characters  of  string  are
     ``0x''  then  string  is expected to be in hexadecimal form;
     otherwise, if the first character of string  is  ``0''  then
     string  is  expected to be in octal form;  otherwise, string
     is expected to be in decimal form.

     Tcl_GetDouble expects string to consist of a  floating-point
     number,  which  is:   white  space;   a  sign; a sequence of
     digits;  a decimal point;  a sequence of digits;  the letter
     ``e'';   and  a  signed decimal exponent.  Any of the fields
     may be omitted, except that  the  digits  either  before  or
     after  the decimal point must be present and if the ``e'' is
     present then it must be followed by the exponent number.

     Tcl_GetBoolean expects string to specify  a  boolean  value.
     If   string   is   any   of  0,  false,  no,  or  off,  then
     Tcl_GetBoolean stores a zero value at *boolPtr.   If  string
     is any of 1, true, yes, or on, then 1 is stored at *boolPtr.
     Any of these values may be abbreviated, and upper-case spel-
     lings are also acceptable.



KEYWORDS

     boolean, conversion, double, floating-point, integer