These functions have meaning only under Hurd. They are needed to get port names that are used in native Hurd API (the RPCs to servers). The .defs and .h files can be found in /include/hurd when all development files are installed (Debian package hurd-dev.) Note that .defs are not included in C programs -- they are used to produce .h files.

file_t
getcwdir (void);

Get file_t port name of current working directory. See <hurd/fs.defs> and <hurd/fs.h>.

int
setcwdir (file_t);
Set current working directory.

file_t
getcrdir (void);
Get file_t port name of current root directory.

int
setcrdir (file_t);

Set current root directory.

file_t
file_name_lookup (const char *file, int flags, mode_t mode);
Open a port to FILE with the given FLAGS and MODE (see <fcntl.h>). The file lookup uses the current root and working directory. Returns a port to the file if successful; otherwise sets errno and returns MACH_PORT_NULL.

file_t
file_name_lookup_under (file_t startdir, const char *file, int flags, mode_t mode);
Open a port to FILE with the given FLAGS and MODE (see <fcntl.h>). The file lookup uses the current root directory, but uses STARTDIR as the "working directory" for file relative names. Returns a port to the file if successful; otherwise sets errno and returns MACH_PORT_NULL.

file_t
file_name_path_lookup (const char *file_name, const char *path, int flags, mode_t mode, char **prefixed_name);
Lookup FILE_NAME and return the node opened with FLAGS & MODE (see hurd_file_name_lookup for details), but a simple file name (without any directory prefixes) will be consecutively prefixed with the pathnames in the : separated list PATH until one succeeds in a successful lookup. If none succeed, then the first error that wasn't ENOENT is returned, or ENOENT if no other errors were returned. If PREFIXED_NAME is non-NULL, then if the result is looked up directly, *PREFIXED_NAME is set to NULL, and if it is looked up using a prefix from PATH, *PREFIXED_NAME is set to malloc'd storage containing the prefixed name.

file_t
file_name_split (const char  file, char **name);
Split FILE into a directory and a name within the directory. The directory lookup uses the current root and working directory. If successful, stores in *NAME a pointer into FILE where the name within directory begins and returns a port to the directory; otherwise sets errno and returns MACH_PORT_NULL.

file_t
directory_name_split (const char *file, char **name);

Split DIRECTORY into a parent directory and a name within the directory. This is the same as file_name_split, but ignores trailing slashes.

FILE *
fopenport (io_t port, const char *mode);
Open a stream on a port. MODE is as for fopen. If successful, this consumes a user reference for PORT (which will be deallocated on fclose).

int
openport (io_t port, int flags);

Open a file descriptor on a port. FLAGS are as for open; flags affected by io_set_openmodes are not changed by this. If successful, this consumes a user reference for PORT (which will be deallocated on close.) See <hurd/io.defs> and <hurd/io.h>.

task_t
pid2task (pid_t pid);

Return the task control port of process PID. On error, sets errno and returns MACH_PORT_NULL.

pid_t
task2pid (task_t task);
Return the PID of the task whose control port is TASK. On error, sets errno and returns -1.

int
geteuids (int n, uid_t *uidset);
Get the effective UID set.

int
seteuids (int n, const uid_t *uidset);
Set the effective UID set.

auth_t
getauth (void);
Get port name of current authentication server. See <hurd/auth.defs> and <hurd/auth.h>.

int
setauth (auth_t);

Set current authentication server.

process_t
getproc (void);
Get port name of current process server. See <hurd/process.defs> and <hurd/process.h>.

int
setproc (process_t);

Set current process server.

mach_port_t
getcttyid (void);
Get the CTTY port.

int
setcttyid (mach_port_t);
Set the CTTY port.

kern_return_t
get_privileged_ports (host_priv_t *host_priv_ptr, device_t *device_master_ptr);
Fetch the host privileged port and device master port from the process server.

mode_t
getumask (void);
Get the current `umask' value without changing it (this glibc functions is available only under GNU Hurd.)

int
vpprintf (io_t port, const char *format, va_list arg);
Write formatted output to PORT, a Mach port supporting the i/o protocol, according to the format string FORMAT, using the argument list in ARG.

thread_t
hurd_thread_self (void);
Return the current thread's thread port. This is a cheap operation (no system call), but it relies on Hurd signal state being set up.

error_t
hurd_thread_cancel (thread_t thread);

Cancel pending operations on THREAD. If it is doing an interruptible RPC, that RPC will now return EINTR; otherwise, the "cancelled" flag will be set, causing the next hurd_check_cancel call to return nonzero or the next interruptible RPC to return EINTR (whichever is called first).

int
hurd_check_cancel (void);

Test and clear the calling thread's "cancelled" flag.