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Top Forums Programming Combine GetOpt And Variadic Function In C Post 303031030 by Corona688 on Wednesday 20th of February 2019 02:41:27 PM
Old 02-20-2019
main and getopt aren't variadic, they're array-based.

So one solution could be converting the variadic arguments into an array.

Code:
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>

void argfunction(char *howmany, ...);

int main(void) {
        argfunction("abc", "atext", "btext", "ctext");
        return(0);
}

void argfunction(char *howmany, ...)
{
        int n=0;
        // Never forget the NULLs, they convert mysterious "why" errors
        //  into "oh, I forgot to assign X" errors
        char *host=NULL, *user=NULL, *pass=NULL, *port=NULL;
        int argc=0;
        char *argv[16];
        va_list ap; // IIRC ap should always be the very last variable declared in a function.
        va_start(ap, howmany);

        argv[0]=""; // just tradition, argv[0] in main() is not an argument

        // checks howmany[0], assigns argv[1].
        // checks howmany[1], assigs argv[2], etc.
        while((argc<(16-2))&&howmany[argc++]) argv[argc]=va_arg(ap, char *);

        argv[argc]=NULL;         // Also traditional that argv[argc] be NULL.

        va_end(ap);

        printf("Howmany is: %s\n", howmany);
        printf("Arguments are:\n");
        for(n=1; n<argc; n++)
                printf("\t%d\t%s\n", n, argv[n]);

        optind=1; // This is global, so reset it

        // You now have argv, argc, and optind just like main to feed getopt with.
}


Last edited by Corona688; 02-20-2019 at 04:07 PM..
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GLCOLORMASK(3G) 														   GLCOLORMASK(3G)

NAME
glColorMask - enable and disable writing of frame buffer color components C SPECIFICATION
void glColorMask( GLboolean red, GLboolean green, GLboolean blue, GLboolean alpha ) PARAMETERS
red, green, blue, alpha Specify whether red, green, blue, and alpha can or cannot be written into the frame buffer. The initial values are all GL_TRUE, indicating that the color components can be written. DESCRIPTION
glColorMask specifies whether the individual color components in the frame buffer can or cannot be written. If red is GL_FALSE, for exam- ple, no change is made to the red component of any pixel in any of the color buffers, regardless of the drawing operation attempted. Changes to individual bits of components cannot be controlled. Rather, changes are either enabled or disabled for entire color components. ERRORS
GL_INVALID_OPERATION is generated if glColorMask is executed between the execution of glBegin and the corresponding execution of glEnd. ASSOCIATED GETS
glGet with argument GL_COLOR_WRITEMASK glGet with argument GL_RGBA_MODE SEE ALSO
glClear(3G), glColor(3G), glColorPointer(3G), glDepthMask(3G), glIndex(3G), glIndexPointer(3G), glIndexMask(3G), glStencilMask(3G) GLCOLORMASK(3G)
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