unistd.h.html

posix标准英文,html格式

<dd>
If <i>sysconf</i>(_SC_V6_LPBIG_OFFBIG) returns -1, the meaning of this value is unspecified. Otherwise, this value is the set of
libraries to be given to the <a href="../utilities/c99.html"><i>c99</i></a> utility to build an application using a programming
model with an <b>int</b> type using at least 32 bits and <b>long</b>, <b>pointer</b>, and <b>off_t</b> types using at least 64
bits.</dd>

<dt>_CS_POSIX_V6_WIDTH_RESTRICTED_ENVS</dt>

<dd>
This value is a &lt;newline&gt;-separated list of names of programming environments supported by the implementation in which the
widths of the <b>blksize_t</b>, <b>cc_t</b>, <b>mode_t</b>, <b>nfds_t</b>, <b>pid_t</b>, <b>ptrdiff_t</b>, <b>size_t</b>,
<b>speed_t</b>, <b>ssize_t</b>, <b>suseconds_t</b>, <b>tcflag_t</b>, <b>useconds_t</b>, <b>wchar_t</b>, and <b>wint_t</b> types are
no greater than the width of type <b>long</b>. The format of each name shall be suitable for use with the <a href=
"../utilities/getconf.html"><i>getconf</i></a> <b>-v</b> option.</dd>
</dl>

<p><sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup> <img src="../images/opt-start.gif" alt="[Option Start]" border="0">
The following symbolic constants are reserved for compatibility with Issue 5:</p>

<p><br>
_CS_XBS5_ILP32_OFF32_CFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFF32_LDFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFF32_LIBS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFF32_LINTFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFFBIG_CFLAGS (<b>LEGACY</b>)<br>
_CS_XBS5_ILP32_OFFBIG_LDFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFFBIG_LIBS (<b>LEGACY</b>)<br>
 _CS_XBS5_ILP32_OFFBIG_LINTFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LP64_OFF64_CFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LP64_OFF64_LDFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LP64_OFF64_LIBS (<b>LEGACY</b>)<br>
 _CS_XBS5_LP64_OFF64_LINTFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LPBIG_OFFBIG_CFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LPBIG_OFFBIG_LDFLAGS (<b>LEGACY</b>)<br>
 _CS_XBS5_LPBIG_OFFBIG_LIBS (<b>LEGACY</b>)<br>
 _CS_XBS5_LPBIG_OFFBIG_LINTFLAGS (<b>LEGACY</b>)<br>
 <img src="../images/opt-end.gif" alt="[Option End]" border="0"><br>
</p>

<p>The following symbolic constants shall be defined for the <a href="../functions/lseek.html"><i>lseek</i>()</a> and <a href=
"../functions/fcntl.html"><i>fcntl</i>()</a> functions and shall have distinct values:</p>

<dl compact>
<dt>SEEK_CUR</dt>

<dd>Set file offset to current plus <i>offset</i>.</dd>

<dt>SEEK_END</dt>

<dd>Set file offset to EOF plus <i>offset</i>.</dd>

<dt>SEEK_SET</dt>

<dd>Set file offset to <i>offset</i>.</dd>
</dl>

<p>The following symbolic constants shall be defined as possible values for the <i>function</i> argument to the <a href=
"../functions/lockf.html"><i>lockf</i>()</a> function:</p>

<dl compact>
<dt>F_LOCK</dt>

<dd>Lock a section for exclusive use.</dd>

<dt>F_TEST</dt>

<dd>Test section for locks by other processes.</dd>

<dt>F_TLOCK</dt>

<dd>Test and lock a section for exclusive use.</dd>

<dt>F_ULOCK</dt>

<dd>Unlock locked sections.</dd>
</dl>

<p>The following symbolic constants shall be defined for <a href="../functions/pathconf.html"><i>pathconf</i>()</a>:</p>

<p><br>
 _PC_2_SYMLINKS<br>
_PC_ALLOC_SIZE_MIN<br>
_PC_ASYNC_IO<br>
_PC_CHOWN_RESTRICTED<br>
_PC_FILESIZEBITS<br>
_PC_LINK_MAX<br>
_PC_MAX_CANON<br>
_PC_MAX_INPUT<br>
_PC_NAME_MAX<br>
_PC_NO_TRUNC<br>
_PC_PATH_MAX<br>
_PC_PIPE_BUF<br>
_PC_PRIO_IO<br>
_PC_REC_INCR_XFER_SIZE<br>
_PC_REC_MIN_XFER_SIZE<br>
_PC_REC_XFER_ALIGN<br>
_PC_SYMLINK_MAX<br>
_PC_SYNC_IO<br>
_PC_VDISABLE<br>
</p>

<p>The following symbolic constants shall be defined for <a href="../functions/sysconf.html"><i>sysconf</i>()</a>:</p>

<p><br>
 _SC_2_C_BIND<br>
_SC_2_C_DEV<br>
_SC_2_CHAR_TERM<br>
_SC_2_FORT_DEV<br>
_SC_2_FORT_RUN<br>
_SC_2_LOCALEDEF<br>
_SC_2_PBS<br>
_SC_2_PBS_ACCOUNTING<br>
_SC_2_PBS_CHECKPOINT<br>
_SC_2_PBS_LOCATE<br>
_SC_2_PBS_MESSAGE<br>
_SC_2_PBS_TRACK<br>
_SC_2_SW_DEV<br>
_SC_2_UPE<br>
_SC_2_VERSION<br>
_SC_ADVISORY_INFO<br>
_SC_AIO_LISTIO_MAX<br>
_SC_AIO_MAX<br>
_SC_AIO_PRIO_DELTA_MAX<br>
_SC_ARG_MAX<br>
_SC_ASYNCHRONOUS_IO<br>
_SC_ATEXIT_MAX<br>
_SC_BARRIERS<br>
_SC_BC_BASE_MAX<br>
_SC_BC_DIM_MAX<br>
_SC_BC_SCALE_MAX<br>
_SC_BC_STRING_MAX<br>
_SC_CHILD_MAX<br>
_SC_CLK_TCK<br>
_SC_CLOCK_SELECTION<br>
_SC_COLL_WEIGHTS_MAX<br>
_SC_CPUTIME<br>
_SC_DELAYTIMER_MAX<br>
_SC_EXPR_NEST_MAX<br>
_SC_FSYNC<br>
_SC_GETGR_R_SIZE_MAX<br>
_SC_GETPW_R_SIZE_MAX<br>
_SC_HOST_NAME_MAX<br>
_SC_IOV_MAX<br>
_SC_IPV6<br>
_SC_JOB_CONTROL<br>
_SC_LINE_MAX<br>
_SC_LOGIN_NAME_MAX<br>
_SC_MAPPED_FILES<br>
_SC_MEMLOCK<br>
_SC_MEMLOCK_RANGE<br>
_SC_MEMORY_PROTECTION<br>
_SC_MESSAGE_PASSING<br>
_SC_MONOTONIC_CLOCK<br>
_SC_MQ_OPEN_MAX<br>
_SC_MQ_PRIO_MAX<br>
_SC_NGROUPS_MAX<br>
_SC_OPEN_MAX<br>
_SC_PAGE_SIZE<br>
_SC_PAGESIZE<br>
_SC_PRIORITIZED_IO<br>
_SC_PRIORITY_SCHEDULING<br>
_SC_RAW_SOCKETS<br>
_SC_RE_DUP_MAX<br>
_SC_READER_WRITER_LOCKS<br>
_SC_REALTIME_SIGNALS<br>
_SC_REGEXP<br>
_SC_RTSIG_MAX<br>
_SC_SAVED_IDS<br>
_SC_SEM_NSEMS_MAX<br>
_SC_SEM_VALUE_MAX<br>
_SC_SEMAPHORES<br>
_SC_SHARED_MEMORY_OBJECTS<br>
_SC_SHELL<br>
_SC_SIGQUEUE_MAX<br>
_SC_SPAWN<br>
_SC_SPIN_LOCKS<br>
_SC_SPORADIC_SERVER<br>
_SC_SS_REPL_MAX<br>
_SC_STREAM_MAX<br>
_SC_SYMLOOP_MAX<br>
_SC_SYNCHRONIZED_IO<br>
_SC_THREAD_ATTR_STACKADDR<br>
_SC_THREAD_ATTR_STACKSIZE<br>
_SC_THREAD_CPUTIME<br>
_SC_THREAD_DESTRUCTOR_ITERATIONS<br>
_SC_THREAD_KEYS_MAX<br>
_SC_THREAD_PRIO_INHERIT<br>
_SC_THREAD_PRIO_PROTECT<br>
_SC_THREAD_PRIORITY_SCHEDULING<br>
_SC_THREAD_PROCESS_SHARED<br>
_SC_THREAD_SAFE_FUNCTIONS<br>
_SC_THREAD_SPORADIC_SERVER<br>
_SC_THREAD_STACK_MIN<br>
_SC_THREAD_THREADS_MAX<br>
_SC_THREADS<br>
_SC_TIMEOUTS<br>
_SC_TIMER_MAX<br>
_SC_TIMERS<br>
_SC_TRACE<br>
_SC_TRACE_EVENT_FILTER<br>
_SC_TRACE_EVENT_NAME_MAX<br>
_SC_TRACE_INHERIT<br>
_SC_TRACE_LOG<br>
_SC_TRACE_NAME_MAX<br>
_SC_TRACE_SYS_MAX<br>
_SC_TRACE_USER_EVENT_MAX<br>
_SC_TTY_NAME_MAX<br>
_SC_TYPED_MEMORY_OBJECTS<br>
_SC_TZNAME_MAX<br>
_SC_V6_ILP32_OFF32<br>
_SC_V6_ILP32_OFFBIG<br>
_SC_V6_LP64_OFF64<br>
_SC_V6_LPBIG_OFFBIG<br>
_SC_VERSION<br>
_SC_XBS5_ILP32_OFF32 (<b>LEGACY</b>)<br>
_SC_XBS5_ILP32_OFFBIG (<b>LEGACY</b>)<br>
_SC_XBS5_LP64_OFF64 (<b>LEGACY</b>)<br>
_SC_XBS5_LPBIG_OFFBIG (<b>LEGACY</b>)<br>
_SC_XOPEN_CRYPT<br>
_SC_XOPEN_ENH_I18N<br>
_SC_XOPEN_LEGACY<br>
_SC_XOPEN_REALTIME<br>
_SC_XOPEN_REALTIME_THREADS<br>
_SC_XOPEN_SHM<br>
_SC_XOPEN_STREAMS<br>
_SC_XOPEN_UNIX<br>
_SC_XOPEN_VERSION<br>
</p>

<p>The two constants _SC_PAGESIZE and _SC_PAGE_SIZE may be defined to have the same value.</p>

<p>The following symbolic constants shall be defined for file streams:</p>

<dl compact>
<dt>STDERR_FILENO</dt>

<dd>File number of <i>stderr</i>; 2.</dd>

<dt>STDIN_FILENO</dt>

<dd>File number of <i>stdin</i>; 0.</dd>

<dt>STDOUT_FILENO</dt>

<dd>File number of <i>stdout</i>; 1.</dd>
</dl>

<h5><a name="tag_13_80_03_05"></a>Type Definitions</h5>

<p>The <b>size_t</b>, <b>ssize_t</b>, <b>uid_t</b>, <b>gid_t</b>, <b>off_t</b>, <b>pid_t</b>, and <b>useconds_t</b> types shall be
defined as described in <a href="../basedefs/sys/types.h.html"><i>&lt;sys/types.h&gt;</i></a>.</p>

<p>The <b>intptr_t</b> type shall be defined as described in <a href=
"../basedefs/inttypes.h.html"><i>&lt;inttypes.h&gt;</i></a>.</p>

<h5><a name="tag_13_80_03_06"></a>Declarations</h5>

<p>The following shall be declared as functions and may also be defined as macros. Function prototypes shall be provided.</p>

<pre>
<tt>int          access(const char *, int);
unsigned     alarm(unsigned);
int          chdir(const char *);
int          chown(const char *, uid_t, gid_t);
int          close(int);
size_t       confstr(int, char *, size_t);
<br>
<sup>[<a href="javascript:open_code('XSI')">XSI</a>]</sup><img src="../images/opt-start.gif" alt="[Option Start]" border="0">
char        *crypt(const char *, const char *);
char        *ctermid(char *);
<img src="../images/opt-end.gif" alt="[Option End]" border="0">
int          dup(int);
<br>
int          dup2(int, int);