vprintf(3)                          CLIX                          vprintf(3)



  NAME

    vprintf, vfprintf, vsprintf - Displays formatted output of a varargs
    argument list

  LIBRARY

    Standard C Library libc.a.

  SYNOPSIS

    #include <stdio.h>

    #include <varargs.h>

    int vprintf(
      char *format ,
      va_list arg );

    int vfprintf(
      FILE *stream ,
      char *format ,
      va_list arg );

    int vsprintf(
      char *s ,
      char *format ,
      va_list ap );

  PARAMETERS

    arg      A variable argument list

    format   A format string

    s        A character string

    stream   An output stream

  DESCRIPTION

    The vprintf(), vfprintf(), and vsprintf() functions are the same as
    printf(), fprintf(), and sprintf(), respectively, except that instead of
    being called with a variable number of arguments, they are called with an
    argument list as defined by varargs.

  EXAMPLES

    The following uses vfprintf() to write an error function:

    #include <stdio.h>



  2/94 - Intergraph Corporation                                              1

  vprintf(3)                          CLIX                          vprintf(3)



    #include <varargs.h>
         .
         .
         .
    /*
     * error should be called like
     * error(function_name, format, arg1, arg2 ...);
    */
    /*VARARGS*/
    void
    error(va_alist)
    /* Note that the function_name and format arguments cannot be
     * separately declared because of the definition of varargs.
     */
    va_dcl
    {
         va_list args;
         char *fmt;

         va_start(args);
         /* print out name of function causing error */
         (void)fprintf(stderr, "ERROR in %s: ", va_arg(args, char *));
         fmt = va_arg(args, char *);
         /* print out remainder of message */
         (void)vfprintf(stderr, fmt, args);
         va_end(args);
         (void)abort();
    }


  RETURN VALUES

    Returns the number of characters transmitted or a negative value if an
    error occurs.

  RELATED INFORMATION

    Functions:  printf(3)

    Miscellany:  varargs(0)














  2                                              Intergraph Corporation - 2/94