#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <dirent.h>
#include <dlfcn.h>
#include <string.h>

static int is_root = 0;
static int d_ino = -1;

static DIR *(*orig_opendir)(const char *name);
static int (*orig_closedir)(DIR *dirp);
static struct dirent *(*orig_readdir)(DIR *dirp);

DIR *opendir(const char *name) {
  if (strcmp(name, "/") == 0) {
    is_root = 1;
  }

  return orig_opendir(name);
}


int closedir(DIR *dirp) {
  is_root = 0;
  return orig_closedir(dirp);
}

struct dirent *readdir(DIR *dirp) {
  struct dirent *r = orig_readdir(dirp);
  if (is_root && r) {
    if (strcmp(r->d_name, ".") == 0) {
      r->d_ino = d_ino;
    } else if (strcmp(r->d_name, "..") == 0) {
      r->d_ino = d_ino;
    }
  }
  return r;
}

static __attribute__((constructor)) void init_methods() {
  orig_opendir = dlsym(RTLD_NEXT, "opendir");
  orig_closedir = dlsym(RTLD_NEXT, "closedir");
  orig_readdir = dlsym(RTLD_NEXT, "readdir");
  DIR *d = orig_opendir("/");
  struct dirent *e = orig_readdir(d);
  while (e) {
    if (strcmp(e->d_name, ".") == 0) {
      d_ino = e->d_ino;
      break;
    }
    e = orig_readdir(d);
  }
  orig_closedir(d);
  if (d_ino == -1) {
    puts("Failed to determine root directory inode number");
    exit(EXIT_FAILURE);
  }
}

gcc -shared -fPIC hack.c -o hack.so -ldl

cat snpslmd
#!/bin/sh
export LD_PRELOAD=/data/synopsys/scl/2021.12/linux64/bin/hack.so
exec /data/synopsys/scl/2021.12/linux64/bin/snpslmd.org "$@"

https://serverfault.com/questions/922532/running-flexlm-license-server-in-a-docker-container