getcwd.c 1.9 KB

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  1. /*
  2. * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
  3. * The President and Fellows of Harvard College.
  4. *
  5. * Redistribution and use in source and binary forms, with or without
  6. * modification, are permitted provided that the following conditions
  7. * are met:
  8. * 1. Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * 2. Redistributions in binary form must reproduce the above copyright
  11. * notice, this list of conditions and the following disclaimer in the
  12. * documentation and/or other materials provided with the distribution.
  13. * 3. Neither the name of the University nor the names of its contributors
  14. * may be used to endorse or promote products derived from this software
  15. * without specific prior written permission.
  16. *
  17. * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY AND CONTRIBUTORS ``AS IS'' AND
  18. * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19. * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20. * ARE DISCLAIMED. IN NO EVENT SHALL THE UNIVERSITY OR CONTRIBUTORS BE LIABLE
  21. * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22. * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23. * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24. * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25. * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26. * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27. * SUCH DAMAGE.
  28. */
  29. #include <unistd.h>
  30. #include <errno.h>
  31. /*
  32. * POSIX C function: retrieve current working directory.
  33. * Uses the system call __getcwd(), which does essentially
  34. * all the work.
  35. */
  36. char *
  37. getcwd(char *buf, size_t buflen)
  38. {
  39. int r;
  40. if (buflen < 1) {
  41. errno = EINVAL;
  42. return NULL;
  43. }
  44. r = __getcwd(buf, buflen-1);
  45. if (r < 0) {
  46. return NULL;
  47. }
  48. buf[r] = 0;
  49. return buf;
  50. }