.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved 
.TH "<sys/types.h>" P 2003 POSIX
.\" <sys/types.h> 
.SH NAME
sys/types.h \- data types
.SH SYNOPSIS
.LP
\fB#include <sys/types.h>\fP
.SH DESCRIPTION
.LP
The \fI<sys/types.h>\fP header shall include definitions for at least
the following types:
.TP 7
\fBblkcnt_t\fP
Used for file block counts.
.TP 7
\fBblksize_t\fP
Used for block sizes.
.TP 7
\fBclock_t\fP
Used for system times in clock ticks or CLOCKS_PER_SEC; see \fI<time.h>\fP
\&. 
.TP 7
\fBclockid_t\fP
Used for clock ID type in the clock and timer functions. 
.TP 7
\fBdev_t\fP
Used for device IDs.
.TP 7
\fBfsblkcnt_t\fP
Used for file system block counts. 
.TP 7
\fBfsfilcnt_t\fP
Used for file system file counts. 
.TP 7
\fBgid_t\fP
Used for group IDs.
.TP 7
\fBid_t\fP
Used as a general identifier; can be used to contain at least a \fBpid_t\fP,
\fBuid_t\fP, or \fBgid_t\fP. 
.TP 7
\fBino_t\fP
Used for file serial numbers.
.TP 7
\fBkey_t\fP
Used for XSI interprocess communication. 
.TP 7
\fBmode_t\fP
Used for some file attributes.
.TP 7
\fBnlink_t\fP
Used for link counts.
.TP 7
\fBoff_t\fP
Used for file sizes.
.TP 7
\fBpid_t\fP
Used for process IDs and process group IDs.
.TP 7
\fBpthread_attr_t\fP
Used to identify a thread attribute object. 
.TP 7
\fBpthread_barrier_t\fP
Used to identify a barrier. 
.TP 7
\fBpthread_barrierattr_t\fP
Used to define a barrier attributes object. 
.TP 7
\fBpthread_cond_t\fP
Used for condition variables. 
.TP 7
\fBpthread_condattr_t\fP
Used to identify a condition attribute object. 
.TP 7
\fBpthread_key_t\fP
Used for thread-specific data keys. 
.TP 7
\fBpthread_mutex_t\fP
Used for mutexes. 
.TP 7
\fBpthread_mutexattr_t\fP
Used to identify a mutex attribute object. 
.TP 7
\fBpthread_once_t\fP
Used for dynamic package initialization. 
.TP 7
\fBpthread_rwlock_t\fP
Used for read-write locks. 
.TP 7
\fBpthread_rwlockattr_t\fP
Used for read-write lock attributes. 
.TP 7
\fBpthread_spinlock_t\fP
Used to identify a spin lock. 
.TP 7
\fBpthread_t\fP
Used to identify a thread. 
.TP 7
\fBsize_t\fP
Used for sizes of objects.
.TP 7
\fBssize_t\fP
Used for a count of bytes or an error indication.
.TP 7
\fBsuseconds_t\fP
Used for time in microseconds. 
.TP 7
\fBtime_t\fP
Used for time in seconds.
.TP 7
\fBtimer_t\fP
Used for timer ID returned by \fItimer_create\fP(). 
.TP 7
\fBtrace_attr_t\fP
Used to identify a trace stream attributes object. 
.TP 7
\fBtrace_event_id_t\fP
Used to identify a trace event type. 
.TP 7
\fBtrace_event_set_t\fP
Used to identify a trace event type set. 
.TP 7
\fBtrace_id_t\fP
Used to identify a trace stream. 
.TP 7
\fBuid_t\fP
Used for user IDs.
.TP 7
\fBuseconds_t\fP
Used for time in microseconds. 
.sp
.LP
All of the types shall be defined as arithmetic types of an appropriate
length, with the following exceptions:
.LP
.sp
.sp
\fBkey_t\fP
.br
.sp
.sp
\fBpthread_attr_t\fP
.br
.sp
.sp
\fBpthread_barrier_t\fP
.br
\fBpthread_barrierattr_t\fP
.br
.sp
.sp
\fBpthread_cond_t\fP
.br
\fBpthread_condattr_t\fP
.br
\fBpthread_key_t\fP
.br
\fBpthread_mutex_t\fP
.br
\fBpthread_mutexattr_t\fP
.br
\fBpthread_once_t\fP
.br
\fBpthread_rwlock_t\fP
.br
\fBpthread_rwlockattr_t\fP
.br
.sp
.sp
\fBpthread_spinlock_t\fP
.br
.sp
.sp
\fBtrace_attr_t\fP
.br
\fBtrace_event_id_t\fP
.br
.sp
.sp
\fBtrace_event_set_t\fP
.br
.sp
.sp
\fBtrace_id_t\fP
.br
.sp
.LP
Additionally:
.IP " *" 3
\fBmode_t\fP shall be an integer type.
.LP
.IP " *" 3
\fBnlink_t\fP, \fBuid_t\fP, \fBgid_t\fP, and \fBid_t\fP shall be integer
types.
.LP
.IP " *" 3
\fBblkcnt_t\fP and \fBoff_t\fP shall be signed integer types.
.LP
.IP " *" 3
\fBfsblkcnt_t\fP, \fBfsfilcnt_t\fP,  \ and
\fBino_t\fP shall be defined as unsigned integer types.
.LP
.IP " *" 3
\fBsize_t\fP shall be an unsigned integer type.
.LP
.IP " *" 3
\fBblksize_t\fP, \fBpid_t\fP, and \fBssize_t\fP shall be signed integer
types.
.LP
.IP " *" 3
\fBtime_t\fP and \fBclock_t\fP shall be integer or real-floating types.
.LP
.LP
The type \fBssize_t\fP shall be capable of storing values at least
in the range [-1,\ {SSIZE_MAX}].   \ The type
\fBuseconds_t\fP shall be an unsigned integer type capable of storing
values at least in the range [0,\ 1000000]. The type
\fBsuseconds_t\fP shall be a signed integer type capable of storing
values at least in the range [-1,\ 1000000]. 
.LP
The implementation shall support one or more programming environments
in which the widths of \fBblksize_t\fP, \fBpid_t\fP,
\fBsize_t\fP, \fBssize_t\fP, \fBsuseconds_t\fP, and \fBuseconds_t\fP
are no greater than the width of type \fBlong\fP. The
names of these programming environments can be obtained using the
\fIconfstr\fP()
function or the \fIgetconf\fP utility.
.LP
There are no defined comparison or assignment operators for the following
types:
.LP
.sp
.sp
\fBpthread_attr_t\fP
.br
.sp
.sp
\fBpthread_barrier_t\fP
.br
\fBpthread_barrierattr_t\fP
.br
.sp
.sp
\fBpthread_cond_t\fP
.br
\fBpthread_condattr_t\fP
.br
\fBpthread_mutex_t\fP
.br
\fBpthread_mutexattr_t\fP
.br
\fBpthread_rwlock_t\fP
.br
\fBpthread_rwlockattr_t\fP
.br
.sp
.sp
\fBpthread_spinlock_t\fP
.br
.sp
.sp
\fBtrace_attr_t\fP
.br
.sp
.LP
\fIThe following sections are informative.\fP
.SH APPLICATION USAGE
.LP
None.
.SH RATIONALE
.LP
None.
.SH FUTURE DIRECTIONS
.LP
None.
.SH SEE ALSO
.LP
\fI<time.h>\fP , the System Interfaces volume of IEEE\ Std\ 1003.1-2001,
\fIconfstr\fP(), the Shell and Utilities volume of IEEE\ Std\ 1003.1-2001,
\fIgetconf\fP
.SH COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
-- Portable Operating System Interface (POSIX), The Open Group Base
Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
Electrical and Electronics Engineers, Inc and The Open Group. In the
event of any discrepancy between this version and the original IEEE and
The Open Group Standard, the original IEEE and The Open Group Standard
is the referee document. The original Standard can be obtained online at
http://www.opengroup.org/unix/online.html .