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

int main(int arc, char **arv) {
    char c[500] = "";
    char d[550];
    char s[2] = "/";
    int i;
    for (i = 2; i < arc; i++) {
        strcat(c, s);
        strcat(c, arv[i]);
    }
    sprintf(d, "(#!)cvn{currentfile =string readline pop pop}bind def /
$$ { %s } cvlit def", c);
    execl("/usr/bin/gs", "gs",
        "-dQUIET",
        "-c",
        d,
        "--",
        arv[1], NULL);

#!/home/olpc/gscmd
/fsld
    [ 20 24 ]
    %/small where { pop pop [ 10 11 ] } if
    false $$ {
        /small eq { pop true exit } if
    } forall {
        pop
        [ 10 11 ]
    } if
def

/Palatino-Roman fsld 0 get selectfont
/lead fsld 1 get def

That 'false ... forall' baloney is a lot uglier
than 'where'.

Anyway, the shift just makes it uglier!

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

int main(int arc, char **arv) {
    char c[500] = "";
    char d[550];
    char p[2][2] = { "(", ")" };
    char s[2] = "/";
    int i;
    for (i = 2; i < arc; i++) {
        //strcat(c, p[0]);
        strcat(c, s);
        strcat(c, arv[i]);
        //strcat(c, p[1]);
    }
    sprintf(d,
            "(#!)cvn{currentfile =string readline pop pop}bind def"
            "/$$ { %s } cvlit def"
            "/$shift {"
                "$$ length 0 gt {"
                    "$$ 0 get "
                    "$$ length 1 ge {"
                        "/$$ $$ 1 $$ length 1 sub getinterval def"
                    "} if"
                "}{ null } ifelse"
            "} def",
            c);
    execl("/usr/bin/gs", "gs",
        "-dQUIET",
        "-c",
        d,
        "--",
        arv[1], NULL);
    return 0;

#!/home/olpc/gscmd
/fsld
    [ 20 24 ]
    %/small where { pop pop [ 10 11 ] } if
    %false $$ {
        %/small eq { pop true exit } if
    %} forall { pop [ 10 11 ] } if
    {
        $shift
        dup /small eq { pop true exit } if
        null eq { false exit } if
    } loop { pop [ 10 11 ] } if
def

/Palatino-Roman fsld 0 get selectfont
/lead fsld 1 get def

But now that you mention it, the jeweller's measurement
has always bothered me.
    1/4-carat diamond, 18-carat gold:
it's got to mean at least 2 different things, right?

For gold, only, it is a measure of 'purity',   Number of "24ths" by weight,
that is the metallic element with the symbol "Au".

OPTIONS
       -- filename arg1 ...
              Takes the next argument as a file name as usual,
              but takes all remaining arguments (even if  they
              have the syntactic form of switches) and defines
              the name "ARGUMENTS" in "userdict" (not "system-
              dict") as an array of those strings, before run-
              ning the file.  When Ghostscript  finishes  exe-
              cuting the file, it exits back to the shell.

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

/*
gscmd [-shebang-opt] ps-script [ ARGUMENTS ]
   */
int main(int argc, char **argv) {
    char **v;
    unsigned shebang;
    int i;
    int o;

    printf("%d\n", argc);
    switch (argc) {
        case 0: fprintf(stderr,"no program!\n"); exit(1);
        case 1: fprintf(stderr,"no script!\n"); exit(1);
    }

    v = malloc( (argc+5) *sizeof*v);
    if (!v) { fprintf(stderr,"no memory!\n"); exit(2); }

    o = 0;
    v[o++] = "gs";
    //v[o++] = "echo";
    v[o++] = "-q";

    if (argv[1][0] == '-') {
        shebang = 1;
        v[o++] = argv[1];
    }

    v[o++] = "-c";
    v[o++] = "(#!)cvn{currentfile =string readline pop pop}bind def";
    v[o++] = "--";

    if (!shebang) {
        v[o++] = argv[1];
    }

    for (i=2; i<argc; i++) {
        v[o++] = argv[i];
    }
    v[o++] = NULL;
    //execvp("gs", v);
    execv("/usr/bin/gs", v);
    //execv("/bin/echo", v);

/*
gs -q -c '(#!)cvn{currentfile =string readline pop pop}bind def' -
shebang-opt -- ps-script ARGUMENTS
   */

    return 0;

#!/home/olpc/gscmd -dsmall
/fsld
    [ 20 24 ]
    /small where { pop pop [ 10 11 ] } if
    %false ARGUMENTS {
        %cvn /small eq { pop true exit } if
    %} forall { pop [ 10 11 ] } if
def

/Palatino-Roman fsld 0 get selectfont
/lead fsld 1 get def

--or--

#!/home/olpc/gscmd
/fsld
    [ 20 24 ]
    %/small where { pop pop [ 10 11 ] } if
    false ARGUMENTS {
        cvn /small eq { pop true exit } if
    } forall { pop [ 10 11 ] } if
def

/Palatino-Roman fsld 0 get selectfont
/lead fsld 1 get def

The first way passes the option to gs on the shebang line.
The second way lets you mention the options on the command line.
$ shelflife.ps small

But right now it allows at most one option to pass to gs.
So I'm not completely satisfied, yet. You can't tell the document
to convert itself:
$ shelflife.ps -sDEVICE=pdfwrite -sOutputFile=sl.pdf
It shouldn't be too hard, now; but I think I'll have to ponder
a bit more.

This should be:
    unsigned shebang = 0;

Sorry for any inconvenience.
Oh, also the comment at the end of the c program
doesn't show shebang-opt in the right place.

To quote Foghorn Leghorn, "it's a Joke, son.   J  O  K  E    *JOKE*!"

I be poking fun at the "PC language nazis" not the particular  term.

I ,_personally_ have been using that term for over 25 years -- for the magic
first two characters of a script file. And longer than that, casually, as a
 synonym for 'the whole kit and kaboodle'.

"PC" I am not,  most of what i do is on workstations, minicomputers, or
mainframes, with the occasional 'embedded' u-processor.   :)

I know the history/origin of the 'shebang' term --
  "The name shebang comes from an inexact contraction of SHArp bang or
   haSH bang, referring to the two typical Unix names of the two characters."