sys_types.h(0p)

1<sys/types.h>(0P)          POSIX Programmer's Manual         <sys/types.h>(0P)
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NAME

6       sys/types.h - data types
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SYNOPSIS

9       #include <sys/types.h>
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DESCRIPTION

12       The  <sys/types.h>  header  shall  include definitions for at least the
13       following types:
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15       blkcnt_t
16              Used for file block counts.
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18       blksize_t
19              Used for block sizes.
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21       clock_t
22              Used for system times in  clock  ticks  or  CLOCKS_PER_SEC;  see
23              <time.h> .
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25       clockid_t
26              Used for clock ID type in the clock and timer functions.
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28       dev_t  Used for device IDs.
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30       fsblkcnt_t
31              Used for file system block counts.
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33       fsfilcnt_t
34              Used for file system file counts.
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36       gid_t  Used for group IDs.
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38       id_t   Used  as a general identifier; can be used to contain at least a
39              pid_t, uid_t, or gid_t.
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41       ino_t  Used for file serial numbers.
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43       key_t  Used for XSI interprocess communication.
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45       mode_t Used for some file attributes.
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47       nlink_t
48              Used for link counts.
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50       off_t  Used for file sizes.
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52       pid_t  Used for process IDs and process group IDs.
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54       pthread_attr_t
55              Used to identify a thread attribute object.
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57       pthread_barrier_t
58              Used to identify a barrier.
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60       pthread_barrierattr_t
61              Used to define a barrier attributes object.
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63       pthread_cond_t
64              Used for condition variables.
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66       pthread_condattr_t
67              Used to identify a condition attribute object.
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69       pthread_key_t
70              Used for thread-specific data keys.
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72       pthread_mutex_t
73              Used for mutexes.
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75       pthread_mutexattr_t
76              Used to identify a mutex attribute object.
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78       pthread_once_t
79              Used for dynamic package initialization.
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81       pthread_rwlock_t
82              Used for read-write locks.
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84       pthread_rwlockattr_t
85              Used for read-write lock attributes.
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87       pthread_spinlock_t
88              Used to identify a spin lock.
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90       pthread_t
91              Used to identify a thread.
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93       size_t Used for sizes of objects.
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95       ssize_t
96              Used for a count of bytes or an error indication.
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98       suseconds_t
99              Used for time in microseconds.
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101       time_t Used for time in seconds.
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103       timer_t
104              Used for timer ID returned by timer_create().
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106       trace_attr_t
107              Used to identify a trace stream attributes object.
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109       trace_event_id_t
110              Used to identify a trace event type.
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112       trace_event_set_t
113              Used to identify a trace event type set.
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115       trace_id_t
116              Used to identify a trace stream.
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118       uid_t  Used for user IDs.
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120       useconds_t
121              Used for time in microseconds.
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124       All of the types shall be defined as arithmetic types of an appropriate
125       length, with the following exceptions:
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127       key_t
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130       pthread_attr_t
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133       pthread_barrier_t
134       pthread_barrierattr_t
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136
137       pthread_cond_t
138       pthread_condattr_t
139       pthread_key_t
140       pthread_mutex_t
141       pthread_mutexattr_t
142       pthread_once_t
143       pthread_rwlock_t
144       pthread_rwlockattr_t
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146
147       pthread_spinlock_t
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149
150       trace_attr_t
151       trace_event_id_t
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153
154       trace_event_set_t
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156
157       trace_id_t
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159
160       Additionally:
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162        * mode_t shall be an integer type.
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164        * nlink_t, uid_t, gid_t, and id_t shall be integer types.
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166        * blkcnt_t and off_t shall be signed integer types.
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168        * fsblkcnt_t, fsfilcnt_t, and ino_t shall be defined as unsigned inte‐
169          ger types.
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171        * size_t shall be an unsigned integer type.
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173        * blksize_t, pid_t, and ssize_t shall be signed integer types.
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175        * time_t and clock_t shall be integer or real-floating types.
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177       The type ssize_t shall be capable of storing values  at  least  in  the
178       range  [-1, {SSIZE_MAX}].   The  type  useconds_t  shall be an unsigned
179       integer  type  capable  of  storing  values  at  least  in  the   range
180       [0, 1000000]. The type suseconds_t shall be a signed integer type capa‐
181       ble of storing values at least in the range [-1, 1000000].
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183       The implementation shall support one or more  programming  environments
184       in  which the widths of blksize_t, pid_t, size_t, ssize_t, suseconds_t,
185       and useconds_t are no greater than the width of type long. The names of
186       these  programming  environments  can  be  obtained using the confstr()
187       function or the getconf utility.
188
189       There are no defined comparison or assignment operators for the follow‐
190       ing types:
191
192       pthread_attr_t
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194
195       pthread_barrier_t
196       pthread_barrierattr_t
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199       pthread_cond_t
200       pthread_condattr_t
201       pthread_mutex_t
202       pthread_mutexattr_t
203       pthread_rwlock_t
204       pthread_rwlockattr_t
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207       pthread_spinlock_t
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209
210       trace_attr_t
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212
213       The following sections are informative.
214

APPLICATION USAGE

216       None.
217

RATIONALE

219       None.
220

FUTURE DIRECTIONS

222       None.
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COPYRIGHT

229       Portions of this text are reprinted and reproduced in  electronic  form
230       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
231       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
232       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
233       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
234       event of any discrepancy between this version and the original IEEE and
235       The Open Group Standard, the original IEEE and The Open Group  Standard
236       is  the  referee document. The original Standard can be obtained online
237       at http://www.opengroup.org/unix/online.html .
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241IEEE/The Open Group                  2003                    <sys/types.h>(0P)