for when you really just need to run a bit of C logic from a bash script

inline_c.sh

#!/bin/bash
TMPFILE=$(mktemp)
cc -Wall -Wextra -Wshadow -Os -lm -o ${TMPFILE} -x c <(tail -n+$(awk '/^exit$/ { print NR + 1 }' $0) $0) && chmod +x ${TMPFILE} && ${TMPFILE} "$@"
rm ${TMPFILE}
exit

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

int main(const int argc, const char ** const argv) {
    fprintf(stderr, "hello world\n");
    
    for (int iarg = 1; iarg < argc; iarg++)
        fprintf(stderr, "argument %d is %s\n", iarg, argv[iarg]);
            
    fprintf(stderr, "stdin is %sa tty\n", isatty(STDIN_FILENO) ? "" : "not ");
}