texinfo include HTML header from file

Question

Since I couldn't find an answer and doing the job my self didn't seem to hard, I wrote a tiny C program to do the job for me. It did the job perfectly in my case!

Ofcourse, if there is an option in Texinfo that does the job, that would be a proper answer, this is just a remedy to get things temporarily going for my self.

#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#define ADDTOHEADER "             \n\
<script type=\"text/javascript\"  \n\
  src=\"http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML\">\n\
</head>"


void
addtexttohtml(char *filename)
{
  char toadd[]=ADDTOHEADER;
  size_t len=0;
  ssize_t read;
  FILE *in, *out;
  char tmpname[]="tmp457204598345.html", *line=NULL;

  in=fopen(filename, "r");
  out=fopen(tmpname, "w");
  if (in == NULL) exit(EXIT_FAILURE);
  if (out == NULL) exit(EXIT_FAILURE);

  while ((read = getline(&line, &len, in)) != -1)
    {
      if(strcmp(line, "</head>\n")==0) break;
      fprintf(out, "%s", line);
    }

  fprintf(out, "%s", toadd);

  while ((read = getline(&line, &len, in)) != -1)
    fprintf(out, "%s", line);

  if(line)
    free(line);

  fclose(in);
  fclose(out);

  rename(tmpname, filename);
}

int
main(int argc, char *argv[])
{
  int i;

  for(i=1;i<argc;i++)
    addtexttohtml(argv[i]);

  return 0;
}

This program can easily be compiled with $ gcc addtoheader.c.

Then we can easily put the compiled program (by default it should be called a.out) with the HTML files and run:

$ a.out *.html

You can just change the macro for any text you want.