A link in PDF

create-pdf.c

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <cairo/cairo.h>
#include <cairo/cairo-pdf.h>

void main()
{
  // Creating a cairo PDF Surface
  cairo_surface_t *csurface = cairo_pdf_surface_create("/home/kenji/a.pdf", 500, 400);
  // Creating a cairo context
  cairo_t *ctx = cairo_create(csurface);
  // Creating rectangle in PDF
  cairo_rectangle(ctx, 0.0, 0.0, 400, 300);
  // Changing rectangle bacground color to Blue
  cairo_set_source_rgb(ctx, 0.0, 0.0, 0.5);
  cairo_fill(ctx);
  // Moving to (10, 10) position in PDF
  cairo_move_to(ctx, 10.0, 10.0);
  // Changing text color to Yellow
  cairo_set_source_rgb(ctx, 1.0, 1.0, 0.0);
  // Writing some text to PDF
  cairo_tag_begin(ctx, CAIRO_TAG_LINK, "uri='https://google.com/'");
  cairo_show_text(ctx, "Hello PDF :-)");
  cairo_tag_end(ctx, CAIRO_TAG_LINK);
  cairo_show_page(ctx);
  // Destroying cairo context
  cairo_destroy(ctx);
  cairo_surface_flush(csurface);
  // Destroying PDF surface
  cairo_surface_destroy(csurface);
  // Opening PDF File
  if (!fork()) {
    execlp("xdg-open", "xdg-open", "/home/kenji/a.pdf", NULL);
    exit(0);
  }
}

$ gcc -l cairo create-pdf.c
$ ./a.out