WSTestUTF8Symbol (C Function)

int WSTestUTF8Symbol(WSLINK l, const unsigned char *s, int n)

tests that the next expression on the WSTP connection specified by l is a symbol with the value s, a UTF-8 encoded string of length n.

Details

  • WSTestUTF8Symbol() fails if the current expression on the link l is not a symbol, or if the value of the symbol does not match s.
  • WSTestUTF8Symbol() returns 0 in the event of an error, and a nonzero value if the function succeeds.
  • Use WSError() to retrieve the error code if WSTestUTF8Symbol() fails.
  • WSTestUTF8Symbol() will reset the stream pointer to the expression on the link just prior to calling WSTestUTF8Symbol()if the function fails. This operation behaves as if the programmer called WSCreateMark(link); WSTestUTF8Symbol(…); WSSeekToMark(…).
  • WSTestUTF8Symbol() is declared in the WSTP header file wstp.h.

Examples

Basic Examples  (1)

#include "wstp.h"

/* A function for testing the next symbol on the link */

void f(WSLINK l)
{
    const unsigned char theSymbol[5];

    theSymbol[0] = 'L';
    theSymbol[1] = 'i';
    theSymbol[2] = 's';
    theSymbol[3] = 't';

    if(! WSTestUTF8Symbol(l, (const unsigned char *)theSymbol,
        4))
    { /* The next expression on the link is not List */ }
    else
    { /* The next expression on the link is List */ }
}