Newer
Older
<li><code>ENOTSOCK</code>.
The argument s is not a socket.
<li><code>EOPNOTSUPP</code>.
Some bit in the flags argument is inappropriate for the socket type.
<li><code>EPIPE</code>.
The local end has been shut down on a connection oriented socket.
In this case the process will also receive a SIGPIPE unless
MSG_NOSIGNAL is set.
</ul>
<h3><a name="recv">2.12.8 <code>recv</code></a></h3>
<p>
<b>Function Prototype:</b>
</p>
<pre>
7017
7018
7019
7020
7021
7022
7023
7024
7025
7026
7027
7028
7029
7030
7031
7032
7033
7034
7035
7036
7037
7038
7039
7040
7041
ssize_t recv(int sockfd, void *buf, size_t len, int flags);
</pre>
<p>
<b>Description:</b>
The <code>recv()</code> call is identical to
<a href="#recvfrom"><code>recvfrom()</code></a> with a NULL
<code>from</code> parameter.
<p>
</p>
<p>
<b>Input Parameters:</b>
</p>
<ul>
</li>
<li>sockfd</code>: Socket descriptor of socket </li>
<li>buf</code>: Buffer to receive data </li>
<li>len</code>: Length of buffer </li>
<li>flags</code>: Receive flags </li>
</ul>
<p>
<b>Returned Values:</b>
see <a href="#recvfrom"><code>recvfrom()</code></a>.
Zero on success.
</p>
<h3><a name="recvfrom">2.12.9 <code>recvfrom</code></a></h3>
<p>
<b>Function Prototype:</b>
</p>
<pre>
7048
7049
7050
7051
7052
7053
7054
7055
7056
7057
7058
7059
7060
7061
7062
7063
7064
7065
7066
7067
7068
7069
7070
7071
7072
7073
7074
7075
ssize_t recvfrom(int sockfd, void *buf, size_t len, int flags,
struct sockaddr *from, socklen_t *fromlen);
</pre>
<p>
<b>Description:</b>
<code>recvfrom()</code> receives messages from a socket, and may be used to receive
data on a socket whether or not it is connection-oriented.
</p>
<p>
If <code>from</code> is not NULL, and the underlying protocol provides the source
address, this source address is filled in. The argument <code>fromlen</code>
initialized to the size of the buffer associated with <code>from</code>, and modified
on return to indicate the actual size of the address stored there.
</p>
<p>
<b>Input Parameters:</b>
</p>
<ul>
<li><code>sockfd</code>: Socket descriptor of socket.</li>
<li><code>buf</code>: Buffer to receive data.</li>
<li><code>len</code>: Length of buffer.</li>
<li><code>flags</code>: Receive flags.</li>
<li><code>from</code>: Address of source.</li>
<li><code>fromlen</code>: The length of the address structure.</li>
</ul>
<p>
<b>Returned Values:</b>
On success, returns the number of characters sent.
On error, -1 is returned, and <a href="#ErrnoAccess"><code>errno</code></a> is set appropriately:
7077
7078
7079
7080
7081
7082
7083
7084
7085
7086
7087
7088
7089
7090
7091
7092
7093
7094
7095
7096
7097
7098
7099
7100
7101
7102
7103
</p>
<ul>
<li><code>EAGAIN</code>.
The socket is marked non-blocking and the receive operation would block,
or a receive timeout had been set and the timeout expired before data
was received.
<li><code>EBADF</code>.
The argument <code>sockfd</code> is an invalid descriptor.
<li><code>ECONNREFUSED</code>.
A remote host refused to allow the network connection (typically because
it is not running the requested service).
<li><code>EFAULT</code>.
The receive buffer pointer(s) point outside the process's address space.
<li><code>EINTR</code>.
The receive was interrupted by delivery of a signal before any data were
available.
<li><code>EINVAL</code>.
Invalid argument passed.
<li><code>ENOMEM</code>.
Could not allocate memory.
<li><code>ENOTCONN</code>.
The socket is associated with a connection-oriented protocol and has
not been connected.
<li><code>ENOTSOCK</code>.
The argument <code>sockfd</code> does not refer to a socket.
</ul>
<h3><a name="setsockopt">2.12.10 <code>setsockopt</code></a></h3>
<p>
<b>Function Prototype:</b>
</p>
<pre>
int setsockopt(int sockfd, int level, int option,
const void *value, socklen_t value_len);
</pre>
<p>
<b>Description:</b>
<code>setsockopt()</code> sets the option specified by the <code>option</code> argument,
at the protocol level specified by the <code>level</code> argument, to the value
pointed to by the <code>value</code> argument for the socket associated with the
file descriptor specified by the <code>sockfd</code> argument.
</p>
<p>
The <code>level</code> argument specifies the protocol level of the option. To set
options at the socket level, specify the level argument as SOL_SOCKET.
</p>
<p>
See <code>sys/socket.h</code> for a complete list of values for the <code>option</code> argument.
</p>
<p>
<b>Input Parameters:</b>
</p>
<ul>
<li><code>sockfd</code>: Socket descriptor of socket
<li><code>level</code>: Protocol level to set the option
<li><code>option</code>: identifies the option to set
<li><code>value</code>: Points to the argument value
<li><code>value_len</code>: The length of the argument value
</ul>
<p>
<b>Returned Values:</b>
On success, returns the number of characters sent.
On error, -1 is returned, and <a href="#ErrnoAccess"><code>errno</code></a> is set appropriately:
7141
7142
7143
7144
7145
7146
7147
7148
7149
7150
7151
7152
7153
7154
7155
7156
7157
7158
7159
7160
7161
7162
7163
</p>
<ul>
<li><code>BADF</code>.
The <code>sockfd</code> argument is not a valid socket descriptor.
<li><code>DOM</code>.
The send and receive timeout values are too big to fit into the
timeout fields in the socket structure.
<li><code>INVAL</code>.
The specified option is invalid at the specified socket <code>level</code> or the
socket has been shut down.
<li><code>ISCONN</code>.
The socket is already connected, and a specified option cannot be set
while the socket is connected.
<li><code>NOPROTOOPT</code>.
The <code>option</code> is not supported by the protocol.
<li><code>NOTSOCK</code>.
The <code>sockfd</code> argument does not refer to a socket.
<li><code>NOMEM</code>.
There was insufficient memory available for the operation to complete.
<li><code>NOBUFS</code>.
Insufficient resources are available in the system to complete the call.
</ul>
<h3><a name="getsockopt">2.12.11 <code>getsockopt</code></a></h3>
<p>
<b>Function Prototype:</b>
</p>
<pre>
int getsockopt(int sockfd, int level, int option,
void *value, socklen_t *value_len);
</pre>
<p>
<b>Description:</b>
<code>getsockopt()</code> retrieve thse value for the option specified by the
<code>option</code> argument for the socket specified by the <code>sockfd</code> argument. If
the size of the option value is greater than <code>value_len</code>, the value
stored in the object pointed to by the <code>value</code> argument will be silently
truncated. Otherwise, the length pointed to by the <code>value_len</code> argument
will be modified to indicate the actual length of the<code>value</code>.
</p>
<p>
The <code>level</code> argument specifies the protocol level of the option. To
retrieve options at the socket level, specify the level argument as
SOL_SOCKET.
</p>
<p>
See <code>sys/socket.h</code>for a complete list of values for the <code>option</code> argument.
</p>
<p>
<b>Input Parameters:</b>
</p>
<ul>
<li><code>sockfd Socket descriptor of socket
<li><code>level Protocol level to set the option
<li><code>option identifies the option to get
<li><code>value Points to the argument value
<li><code>value_len The length of the argument value
</ul>
<p>
<b>Returned Values:</b>
On success, returns the number of characters sent.
On error, -1 is returned, and <a href="#ErrnoAccess"><code>errno</code></a> is set appropriately:
</p>
<ul>
<li><code>BADF</code>.
The <code>sockfd</code> argument is not a valid socket descriptor.</li>
<li><code>INVAL</code>.
The specified option is invalid at the specified socket <code>level</code> or the
socket has been shutdown.</li>
<li><code>NOPROTOOPT</code>.
The <code>option</code> is not supported by the protocol.</li>
<li><code>NOTSOCK</code>.
The <code>sockfd</code> argument does not refer to a socket.</li>
<li><code>NOBUFS
Insufficient resources are available in the system to complete the call.</li>
</ul>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="Data_Structures"><h1>3.0 OS Data Structures</h1></a>
</td>
</tr>
</table>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="ScalarType"><h2>3.1 Scalar Types</h2></a>
</td>
</tr>
</table>
Many of the types used to communicate with NuttX are simple
scalar types. These types are used to provide architecture independence
of the OS from the application. The scalar types used at the NuttX
<ul>
<li>pid_t
<li>size_t
<li>sigset_t
<li>STATUS
<li>time_t
</ul>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="HiddenStructures"><h2>3.2 Hidden Interface Structures</h2></a>
</td>
</tr>
</table>
Several of the types used to interface with NuttX are
structures that are intended to be hidden from the application.
From the standpoint of the application, these structures (and
structure pointers) should be treated as simple handles to reference
OS resources. These hidden structures include:
<ul>
<li>_TCB
<li>mqd_t
<li>sem_t
<li>WDOG_ID
<li>pthread_key_t
</ul>
<p>
In order to maintain portability, applications should not reference
specific elements within these hidden structures. These hidden
structures will not be described further in this user's manual.
</p>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="ErrnoAccess"><h2>3.3 Access to the <code>errno</code> Variable</h2></a>
</td>
</tr>
</table>
A pointer to the thread-specific <code>errno</code> value is available through a
function call:
</p>
#define errno *get_errno_ptr()
int *get_errno_ptr( void )</pre>
<b>Description</b>:
<code>get_errno_ptr()</code> returns a pointer to the thread-specific <code>errno</code> value.
Note that the symbol <code>errno</code> is defined to be <code>get_errno_ptr()</code> so that the usual
access by referencing the symbol <code>errno</code> will work as expected.
</p>
There is a unique, private <code>errno</code> value for each NuttX task.
However, the implementation of <code>errno</code> differs somewhat from the use of
<code>errno</code> in most multi-threaded process environments:
In NuttX, each pthread will also have its own private copy of <code>errno</code> and the
<code>errno</code> will not be shared between pthreads.
This is, perhaps, non-standard but promotes better thread independence.
<p>
<b>Input Parameters</b>: None
<p>
<b>Returned Values</b>:
<p>
<ul>
<li>A pointer to the thread-specific <code>errno</code> value.
</p>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="UserStructures"><h2>3.4 User Interface Structures</h2></a>
</td>
</tr>
</table>
main_t defines the type of a task entry point. main_t is declared
in sys/types.h as:
This structure is used to pass scheduling priorities to and from
NuttX;
NuttX and a user application:
struct timespec
{
time_t tv_sec; /* Seconds */
long tv_nsec; /* Nanoseconds */
};
between NuttX and a MoBY application:
struct mq_attr {
size_t mq_maxmsg; /* Max number of messages in queue */
size_t mq_msgsize; /* Max message size */
unsigned mq_flags; /* Queue flags */
size_t mq_curmsgs; /* Number of messages currently in queue */
};
The following structure defines the action to take for given signal:
struct sigaction
{
union
{
void (*_sa_handler)(int);
void (*_sa_sigaction)(int, siginfo_t *, void *);
} sa_u;
sigset_t sa_mask;
int sa_flags;
};
#define sa_handler sa_u._sa_handler
#define sa_sigaction sa_u._sa_sigaction
The following types is used to pass parameters to/from signal
handlers:
typedef struct siginfo
{
int si_signo;
int si_code;
union sigval si_value;
} siginfo_t;
This defines the type of the struct siginfo si_value field and
is used to pass parameters with signals.
union sigval
{
int sival_int;
void *sival_ptr;
};
The following is used to attach a signal to a message queue to
notify a task when a message is available on a queue.
struct sigevent
{
int sigev_signo;
union sigval sigev_value;
int sigev_notify;
};
7430
7431
7432
7433
7434
7435
7436
7437
7438
7439
7440
7441
7442
7443
7444
7445
7446
7447
7448
7449
7450
7451
7452
7453
7454
7455
7456
7457
7458
7459
7460
7461
7462
<H3>3.4.9 Watchdog Data Types</H3>
<p>
When a watchdog expires, the callback function with this
type is called:
</p>
<pre>
typedef void (*wdentry_t)(int argc, ...);
</pre>
<p>
Where argc is the number of uint32 type arguments that follow.
</p>
The arguments are passed as uint32 values.
For systems where the sizeof(pointer) < sizeof(uint32), the
following union defines the alignment of the pointer within the
uint32. For example, the SDCC MCS51 general pointer is
24-bits, but uint32 is 32-bits (of course).
</p>
<pre>
union wdparm_u
{
void *pvarg;
uint32 *dwarg;
};
typedef union wdparm_u wdparm_t;
</pre>
<p>
For most 32-bit systems, pointers and uint32 are the same size
For systems where sizeof(pointer) > sizeof(uint32), we will
have to do some redesign.
</p>
<table width ="100%">
<tr bgcolor="#e4e4e4">
<td>
<a name="index"><h1>Index</h1></a>
</td>
</tr>
</table>
<li><a href="#accept">accept</a></li>
<li><a href="#mmapxip">BIOC_XIPBASE</a></li>
<li><a href="#dirunistdops">chdir</a></li>
<li><a href="#clockgetres">clock_getres</a></li>
<li><a href="#clockgettime">clock_gettime</a></li>
<li><a href="#ClocksNTimers">Clocks</a></li>
<li><a href="#clocksettime">clock_settime</a></li>
<li><a href="#drvrunistdops">close</a></li>
<li><a href="#dirdirentops">closedir</a></li>
<li><a href="#Data_Structures">Data structures</a></li>
<li><a href="#directoryoperations">Directory operations</a></li>
<li><a href="#driveroperations">Driver operations</a></li>
<li><a href="#drvrunistdops">dup</a></li>
<li><a href="#drvrunistdops">dup2</a></li>
<li><a href="#mmapxip">eXecute In Place (XIP)</a></li>
<li><a href="#fatsupport">FAT File System Support</a></li>
<li><a href="#standardio">fclose</a></li>
<li><a href="#standardio">fdopen</a></li>
<li><a href="#standardio">feof</a></li>
<li><a href="#standardio">ferror</a></li>
<li><a href="#FileSystem">File system, interfaces</a></li>
<li><a href="#FileSystemOverview">File system, overview</a></li>
<li><a href="#standardio">fflush</a></li>
<li><a href="#standardio">fgetc</a></li>
<li><a href="#standardio">fgetpos</a></li>
<li><a href="#standardio">fgets</a></li>
<li><a href="#mmapxip">FIOC_MMAP</a></li>
<li><a href="#standardio">fopen</a></li>
<li><a href="#standardio">fprintf</a></li>
<li><a href="#standardio">fputc</a></li>
<li><a href="#standardio">fputs</a></li>
<li><a href="#standardio">fread</a></li>
<li><a href="#standardio">fseek</a></li>
<li><a href="#standardio">fsetpos</a></li>
<li><a href="#standardio">ftell</a></li>
<li><a href="#standardio">fwrite</a></li>
<li><a href="#dirunistdops">getcwd</a></li>
<li><a href="#standardio">gets</a></li>
<li><a href="#gmtimer">gmtime_r</a></li>
<li><a href="#drvrioctlops">ioctl</a></li>
<li><a href="#listen">listen</a></li>
<li><a href="#localtimer">localtime_r</a></li>
<li><a href="#drvrunistdops">lseek</a></li>
<li><a href="#standardio">mkdir</a></li>
<li><a href="#mktime">mktime</a></li>
<li><a href="#mqclose">mq_close</a></li>
<li><a href="#mqgetattr">mq_getattr</a></li>
<li><a href="#mqnotify">mq_notify</a></li>
<li><a href="#mqopen">mq_open</a></li>
<li><a href="#mqreceive">mq_receive</a></li>
<li><a href="#mqsend">mq_send</a></li>
<li><a href="#mqsetattr">mq_setattr</a></li>
<li><a href="#mqtimedreceive">mq_timedreceive</a></li>
<li><a href="#mqtimedsend">mq_timedsend</a></li>
<li><a href="#drvrfcntlops">open</a></li>
<li><a href="#dirdirentops">opendir</a></li>
</td>
<td valign="top" width="33%">
<li><a href="#poll">poll</a></li>
<li><a href="#drvrpollops">poll.h</a></li>
<li><a href="#standardio">printf</a></li>
<li><a href="#pthreadattrdestroy">pthread_attr_destroy</a></li>
<li><a href="#pthreadattrgetinheritsched">pthread_attr_getinheritsched</a></li>
<li><a href="#pthreadattrgetschedparam">pthread_attr_getschedparam</a></li>
<li><a href="#pthreadattrgetschedpolicy">pthread_attr_getschedpolicy</a></li>
<li><a href="#pthreadattrgetstacksize">pthread_attr_getstacksize</a></li>
<li><a href="#pthreadattrinit">pthread_attr_init</a></li>
<li><a href="#pthreadattrsetinheritsched">pthread_attr_setinheritsched</a></li>
<li><a href="#pthreadattrsetschedparam">pthread_attr_setschedparam</a></li>
<li><a href="#pthreadattrsetschedpolity">pthread_attr_setschedpolicy</a></li>
<li><a href="#pthreadattrsetstacksize">pthread_attr_setstacksize</a></li>
<li><a href="#pthreadbarrierattrinit">pthread_barrierattr_init</a></li>
<li><a href="#pthreadbarrierattrdestroy">pthread_barrierattr_destroy</a></li>
<li><a href="#pthreadbarrierattrgetpshared">pthread_barrierattr_getpshared</a></li>
<li><a href="#pthreadbarrierattrsetpshared">pthread_barrierattr_setpshared</a></li>
<li><a href="#pthreadbarrierdestroy">pthread_barrier_destroy</a></li>
<li><a href="#pthreadbarrierinit">pthread_barrier_init</a></li>
<li><a href="#pthreadbarrierwait">pthread_barrier_wait</a></li>
<li><a href="#pthreadcancel">pthread_cancel</a></li>
<li><a href="#pthreadconaddrinit">pthread_condattr_init</a></li>
<li><a href="#pthreadcondbroadcast">pthread_cond_broadcast</a></li>
<li><a href="#pthreadconddestroy">pthread_cond_destroy</a></li>
<li><a href="#pthreadcondinit">pthread_cond_init</a></li>
<li><a href="#pthreadcondsignal">pthread_cond_signal</a></li>
<li><a href="#pthreadcondtimedwait">pthread_cond_timedwait</a></li>
<li><a href="#pthreadcondwait">pthread_cond_wait</a></li>
<li><a href="#pthreadcreate">pthread_create</a></li>
<li><a href="#pthreaddetach">pthread_detach</a></li>
<li><a href="#pthreadexit">pthread_exit</a></li>
<li><a href="#pthreadgetschedparam">pthread_getschedparam</a></li>
<li><a href="#pthreadgetspecific">pthread_getspecific</a></li>
<li><a href="#Pthread"><i>pthreads</i></a> share some resources.
<li><a href="#pthreadjoin">pthread_join</a></li>
<li><a href="#pthreadkeycreate">pthread_key_create</a></li>
<li><a href="#pthreadkeydelete">pthread_key_delete</a></li>
<li><a href="#pthreadmutexattrdestroy">pthread_mutexattr_destroy</a></li>
<li><a href="#pthreadmutexattrgetpshared">pthread_mutexattr_getpshared</a></li>
<li><a href="#pthreadmutexattrgettype">pthread_mutexattr_gettype</a></li>
<li><a href="#pthreadmutexattrinit">pthread_mutexattr_init</a></li>
<li><a href="#pthreadmutexattrsetpshared">pthread_mutexattr_setpshared</a></li>
<li><a href="#pthreadmutexattrsettype">pthread_mutexattr_settype</a></li>
<li><a href="#pthreadmutexdestrory">pthread_mutex_destroy</a></li>
<li><a href="#pthreadmutexinit">pthread_mutex_init</a></li>
<li><a href="#pthreadmutexlock">pthread_mutex_lock</a></li>
<li><a href="#pthreadmutextrylock">pthread_mutex_trylock</a></li>
<li><a href="#pthreadmutexunlock">pthread_mutex_unlock</a></li>
<li><a href="#pthreadocndattrdestroy">pthread_condattr_destroy</a></li>
<li><a href="#pthreadself">pthread_self</a></li>
<li><a href="#pthreadsetcancelstate">pthread_setcancelstate</a></li>
<li><a href="#pthreadsetschedparam">pthread_setschedparam</a></li>
<li><a href="#pthreadsetspecific">pthread_setspecific</a></li>
<li><a href="#pthreadsigmask">pthread_sigmask</a></li>
<li><a href="#pthreadtestcancelstate">pthread_testcancelstate</a></li>
<li><a href="#pthreadyield">pthread_yield</a></li>
<li><a href="#standardio">puts</a></li>
<li><a href="#mmapxip">RAM disk driver</a></li>
<li><a href="#drvrunistdops">read</a></li>
<li><a href="#dirdirentops">readdir</a></li>
<li><a href="#dirdirentops">readdir_r</a></li>
<li><a href="#recv">recv</a></li>
<li><a href="#recvfrom">recvfrom</a></li>
<li><a href="#standardio">rename</a></li>
<li><a href="#standardio">rmdir</a></li>
<li><a href="#dirdirentops">rewinddir</a></li>
<li><a href="#mmapxip">ROM disk driver</a></li>
<li><a href="#mmapxip">ROMFS</a></li>
<li><a href="#schedgetprioritymax">sched_get_priority_max</a></li>
<li><a href="#schedgetprioritymin">sched_get_priority_min</a></li>
<li><a href="#schedgetrrinterval">sched_get_rr_interval</a></li>
<li><a href="#schedlockcount">sched_lockcount</a></li>
<li><a href="#schedlock">sched_lock</a></li>
<li><a href="#schedsetparam">sched_setparam</a></li>
<li><a href="#schedsetscheduler">sched_setscheduler</a></li>
<li><a href="#schedunlock">sched_unlock</a></li>
<li><a href="#sched_yield">sched_yield</a></li>
<li><a href="#Semaphores">Counting Semaphore Interfaces</a>
<li><a href="#semclose">sem_close</a></li>
<li><a href="#semdestroy">sem_destroy</a></li>
<li><a href="#semgetvalue">sem_getvalue</a></li>
<li><a href="#seminit">sem_init</a></li>
<li><a href="#semopen">sem_open</a></li>
<li><a href="#sempost">sem_post</a></li>
<li><a href="#semtrywait">sem_trywait</a></li>
<li><a href="#semunlink">sem_unlink</a></li>
<li><a href="#semwait">sem_wait</a></li>
<li><a href="#setgetscheduler">sched_getscheduler</a></li>
<li><a href="#dirdirentops">seekdir</a></li>
<li><a href="#send">send</a></li>
<li><a href="#sendto">sendto</a></li>
<li><a href="#setsockopt">setsockopt</a></li>
<li><a href="#sigaction">sigaction</a></li>
<li><a href="#sigaddset">sigaddset</a></li>
<li><a href="#sigdelset">sigdelset</a></li>
<li><a href="#sigemptyset">sigemptyset</a></li>
<li><a href="#sigfillset">sigfillset</a></li>
<li><a href="#sigismember">sigismember</a></li>
<li><a href="#Signals">Signal Interfaces</a>
<li><a href="#sigpending">sigpending</a></li>
<li><a href="#sigprocmask">sigprocmask</a></li>
<li><a href="#sigqueue">sigqueue</a></li>
<li><a href="#sigsuspend">sigsuspend</a></li>
<li><a href="#sigtimedwait">sigtimedwait</a></li>
<li><a href="#sigwaitinfo">sigwaitinfo</a></li>
<li><a href="#standardio">sprintf</a></li>
<li><a href="#standardio">Standard I/O</a></li>
<li><a href="#standardio">stat</a></li>
<li><a href="#standardio">statfs</a></li>
<li><a href="#drvselectops">sys/select.h</a></li>
<li><a href="#drvrioctlops">sys/ioctl.h</a></li>
<li><a href="#taskactivate">task_activate</a></li>
<li><a href="#Task_Control">Task Control Interfaces</a>
<li><a href="#taskcreate">task_create</a></li>
<li><a href="#taskdelete">task_delete</a></li>
<li><a href="#taskinit">task_init</a></li>
<li><a href="#taskrestart">task_restart</a></li>
<li><a href="#Task_Schedule">Task Scheduling Interfaces</a>
<li><a href="#Task_Switch">Task Switching Interfaces</a>
<li><a href="#dirdirentops">telldir</a></li>
<li><a href="#timercreate">timer_create</a></li>
<li><a href="#timerdelete">timer_delete</a></li>
<li><a href="#timergetoverrun">timer_getoverrun</a></li>
<li><a href="#timergettime">timer_gettime</a></li>
<li><a href="#ClocksNTimers">Timers</a></li>
<li><a href="#timersettime">timer_settime</a></li>
<li><a href="#standardio">ungetc</a></li>
<li><a href="#drvrunistdops">unistd.h</a>,
<a href="#dirunistdops">unistd.h</a></li>
<li><a href="#drvrunistdops">unlink</a></li>
<li><a href="#standardio">vfprintf</a></li>
<li><a href="#standardio">vprintf</a></li>
<li><a href="#standardio">vsprintf</a></li>
<li><a href="#Watchdogs">Watchdog Timer Interfaces</a>
<li><a href="#wdcancel">wd_cancel</a></li>
<li><a href="#wdcreate">wd_create</a></li>
<li><a href="#wddelete">wd_delete</a></li>
<li><a href="#wdgettime">wd_gettime</a></li>
<li><a href="#drvrunistdops">write</a></li>