The path argument points to the pathname of a directory. The fd argument is a file descriptor which references a directory. The chdir
function causes this directory to become the current working directory, the starting point for path names not beginning with ``/''.
The fchdir function causes the directory referenced by fd to become the current working directory, the starting point for path searches of
pathnames not beginning with a slahs, '/'.
In order for a directory to become the current directory, a process must have execute (search) access to the directory.
Upon successful completion, a value of 0 is returned. Otherwise, a value of -1 is returned and errno is set to indicate the error.
Chdir will fail and the current working directory will be unchanged if one or more of the following are true:
[ENOTDIR] A component of the path prefix is not a directory.
[EINVAL] The pathname contains a character with the high-order bit set.
[ENAMETOOLONG] A component of a pathname exceeded 63 characters, or an entire path name exceeded 255 characters.
[ENOENT] The named directory does not exist.
[ELOOP] Too many symbolic links were encountered in translating the pathname.
[EACCES] Search permission is denied for any component of the path name.
[EFAULT] Path points outside the process's allocated address space.
[EIO] An I/O error occurred while reading from or writing to the file system.
Fchdir will fail and the current working directory will be unchanged if one or more of the following are true:
[EACCES] Search permission is denied for the directory referenced by the file descriptor.
[ENOTDIR] The file descriptor fd does not reference a directory.
[EBADF] The argument fd is not a valid file descriptor.