Re: Multipurpose binaries with different names

[Paolo Bonzini]

On 07/24/2009 11:25 AM, Jan Engelhardt wrote:
> Hi,
>
>
> when one has a program that does something like
>
>    if(strcmp(argv[0], "gunzip") == 0)
>      uncompress();
>    else
>      compress();
>
> and this program also uses a libtool library, then the - lets use this
> example - just-built "gzip" file will be around 4 kilobytes only, it is
> a libtool wrapper scripts for .libs/gzip. "gunzip" would then be a
> symlink to "gzip", but calling gunzip results in the libtool script
> calling gzip instead, thereby leading to the wrong mode of operation.
>
> This makes it hard to run libtooled programs from within the compilation
> directory. A possible workaround is that the libtool wrapper script
> honors $0 a little more:

Since anyway you have to use install-programs-hook to create the 
multipurpose binary, you can add another name (e.g. gztool) and invoke 
it like "gztool gzip" or "gztool gunzip" while uninstalled:

#ifdef _WIN32
  executable_name = strrchr (argv[0], '\\');
  if (!executable_name || strchr (executable_name, '/'))
    executable_name = strrchr (argv[0], '/');
#else
  executable_name = strrchr (argv[0], '/');
#endif /* _WIN32 */

  if (executable_name)
    executable_name++;
  else
    executable_name = argv[0];

  if (!strcasecmp (executable_name, "gztool" EXEEXT)
      || (EXEEXT[0] && !strcasecmp (executable_name, "gztool")
      || !strcasecmp (executable_name, "lt-gztool" EXEEXT)
      || (EXEEXT[0] && !strcasecmp (executable_name, "lt-gztool")))
    {
      program_name = strdup (argv[1]);
      argv++, argc--;
    }
  else
    {
      int n = strlen (executable_name);
      program_name = strdup (executable_name);

      /* Strip the executable extension if needed.  */
      if (EXEEXT[0]
          && n > strlen (EXEEXT)
          && !strcasecmp (program_name + n - strlen (EXEEXT), EXEEXT))
        program_name[n - strlen (EXEEXT)] = 0;
    }

  if (strcmp (program_name, "gzip"))
    exit (compress ());
  else
    exit (uncompress ());

Make gztool noinst_PROGRAMS and you're done.

Paolo