Question

On GCC Linux, is there a way I can add a file resource to be embedded statically into the C program, and then how would I expand that out to /tmp from main()?

Answer 1

You can use objcopy to embed the resource, and then normal file operations to create the file in /tmp.

If you compile this program:

#include <stdio.h>

extern char _binary_resource_bin_start, _binary_resource_bin_end;

int main() {
  FILE*out = fopen("/tmp/rsrc.bin","wb");
  fwrite(&_binary_resource_bin_start,
    &_binary_resource_bin_end - &_binary_resource_bin_start, 1, out);
  fclose(out);
}

with this makefile:

program: program.o resource.o
    $(CC) -o program program.o resource.o

resource.o: resource.bin
    objcopy -I binary -O elf32-i386 -B i386 resource.bin resource.o

resource.bin:
    echo resource-file-contents > resource.bin

I believe you will get what you want.