slaIntin -


void slaIntin(string, nstrt, ireslt, jflag)


char *string
int *nstrt
long int *ireslt
int *jflag


  Convert free-format input into a long integer.


     *string    char    string containing number to be decoded
     *nstrt     int     where to start decode (1st = 1)
     *ireslt    int     current value of result


     *nstrt     int     advanced to next number
     *ireslt    long    result
     *jflag     int     status: -1 = -OK, 0 = +OK, 1 = null, 2 = error




     1     The reason slaIntin has separate OK status values for +
           and - is to enable minus zero to be detected.   This is
           of crucial importance when decoding mixed-radix numbers.
           For example, an angle expressed as deg, arcmin, arcsec
           may have a leading minus sign but a zero degrees field.

     2     A TAB is interpreted as a space.

     3     The basic format is the sequence of fields ^, where
           # is a sign character + or -, and ^ means a string of
           decimal digits.

4 Spaces

             .  Leading spaces are ignored.

             .  Spaces between the sign and the number are allowed.

             .  Trailing spaces are ignored;  the first signifies
                end of decoding and subsequent ones are skipped.

5 Delimiters

             .  Any character other than +,-,0-9 or space may be
                used to signal the end of the number and terminate

             .  Comma is recognised by slaIntin as a special case;  it
                is skipped, leaving the pointer on the next character.
                See 9, below.

     6     The sign is optional.  The default is +.

     7     A "null result" occurs when the string of characters being
           decoded does not begin with +,- or 0-9, or consists
           entirely of spaces.  When this condition is detected, jflag
           is set to 1 and ireslt is left untouched.

     8     nstrt = 1 for the first character in the string.

     9     On return from slaIntin, nstrt is set ready for the next
           decode - following trailing blanks and any comma.  If a
           delimiter other than comma is being used, nstrt must be
           incremented before the next call to slaIntin, otherwise
           all subsequent calls will return a null result.

10 Errors (jflag=2) occur when

             .  there is a + or - but no number;  or

             .  the number is larger than LONG_MAX.

     11    When an error has been detected, nstrt is left
           pointing to the character following the last
           one used before the error came to light.

     12    See also slaFlotin and slaDfltin.

  P.T.Wallace   Starlink   17 November 1993