'\" et

.TH sys_types.h "0P" 2013 "IEEE/The Open Group" "POSIX Programmer's Manual"

.SH PROLOG

This manual page is part of the POSIX Programmer's Manual.

The Linux implementation of this interface may differ (consult

the corresponding Linux manual page for details of Linux behavior),

or the interface may not be implemented on Linux.

.SH NAME

sys/types.h

\(em data types

.SH SYNOPSIS

.LP

.nf

#include <sys/types.h>

.fi

.SH DESCRIPTION

The

.IR <sys/types.h> 

header shall define at least the following types:

.IP "\fBblkcnt_t\fP" 16

Used for file block counts.

.IP "\fBblksize_t\fP" 16

Used for block sizes.

.IP "\fBclock_t\fP" 16

Used for system times in clock ticks or CLOCKS_PER_SEC; see

.IR <time.h> .

.IP "\fBclockid_t\fP" 16

Used for clock ID type in the clock and timer functions.

.IP "\fBdev_t\fP" 16

Used for device IDs.

.IP "\fBfsblkcnt_t\fP" 16

Used for file system block counts.

.IP "\fBfsfilcnt_t\fP" 16

Used for file system file counts.

.IP "\fBgid_t\fP" 16

Used for group IDs.

.IP "\fBid_t\fP" 16

Used as a general identifier; can be used to contain at least a

.BR pid_t ,

.BR uid_t ,

or

.BR gid_t .

.IP "\fBino_t\fP" 16

Used for file serial numbers.

.IP "\fBkey_t\fP" 16

Used for XSI interprocess communication.

.IP "\fBmode_t\fP" 16

Used for some file attributes.

.IP "\fBnlink_t\fP" 16

Used for link counts.

.IP "\fBoff_t\fP" 16

Used for file sizes.

.IP "\fBpid_t\fP" 16

Used for process IDs and process group IDs.

.IP "\fBpthread_attr_t\fP" 16

Used to identify a thread attribute object.

.IP "\fBpthread_barrier_t\fP" 16

Used to identify a barrier.

.IP "\fBpthread_barrierattr_t\fP" 16

Used to define a barrier attributes object.

.IP "\fBpthread_cond_t\fP" 16

Used for condition variables.

.IP "\fBpthread_condattr_t\fP" 16

Used to identify a condition attribute object.

.IP "\fBpthread_key_t\fP" 16

Used for thread-specific data keys.

.IP "\fBpthread_mutex_t\fP" 16

Used for mutexes.

.IP "\fBpthread_mutexattr_t\fP" 16

Used to identify a mutex attribute object.

.IP "\fBpthread_once_t\fP" 16

Used for dynamic package initialization.

.IP "\fBpthread_rwlock_t\fP" 16

Used for read-write locks.

.IP "\fBpthread_rwlockattr_t\fP" 16

Used for read-write lock attributes.

.IP "\fBpthread_spinlock_t\fP" 16

Used to identify a spin lock.

.IP "\fBpthread_t\fP" 16

Used to identify a thread.

.IP "\fBsize_t\fP" 16

Used for sizes of objects.

.IP "\fBssize_t\fP" 16

Used for a count of bytes or an error indication.

.IP "\fBsuseconds_t\fP" 16

Used for time in microseconds.

.IP "\fBtime_t\fP" 16

Used for time in seconds.

.IP "\fBtimer_t\fP" 16

Used for timer ID returned by

\fItimer_create\fR().

.IP "\fBtrace_attr_t\fP" 16

Used to identify a trace stream attributes object

.IP "\fBtrace_event_id_t\fP" 16

Used to identify a trace event type.

.IP "\fBtrace_event_set_t\fP" 16

Used to identify a trace event type set.

.IP "\fBtrace_id_t\fP" 16

Used to identify a trace stream.

.IP "\fBuid_t\fP" 16

Used for user IDs.

.P

All of the types shall be defined as arithmetic types of an appropriate

length, with the following exceptions:

.P

.nf

.BR pthread_attr_t

.BR pthread_barrier_t

.BR pthread_barrierattr_t

.BR pthread_cond_t

.BR pthread_condattr_t

.BR pthread_key_t

.BR pthread_mutex_t

.BR pthread_mutexattr_t

.BR pthread_once_t

.BR pthread_rwlock_t

.BR pthread_rwlockattr_t

.BR pthread_spinlock_t

.BR pthread_t

.BR trace_attr_t

.BR trace_event_id_t

.BR trace_event_set_t

.BR trace_id_t

.fi

.P

Additionally:

.IP " *" 4

.BR mode_t

shall be an integer type.

.IP " *" 4

.BR dev_t

shall be an integer type.

.IP " *" 4

.BR nlink_t ,

.BR uid_t ,

.BR gid_t ,

and

.BR id_t

shall be integer types.

.IP " *" 4

.BR blkcnt_t

and

.BR off_t

shall be signed integer types.

.IP " *" 4

.BR fsblkcnt_t ,

.BR fsfilcnt_t ,

and

.BR ino_t

shall be defined as unsigned integer types.

.IP " *" 4

.BR size_t

shall be an unsigned integer type.

.IP " *" 4

.BR blksize_t ,

.BR pid_t ,

and

.BR ssize_t

shall be signed integer types.

.IP " *" 4

.BR clock_t

shall be an integer or real-floating type.

.BR time_t

shall be an integer type.

.P

The type

.BR ssize_t

shall be capable of storing values at least in the range

[\(mi1,\ {SSIZE_MAX}].

.P

The type

.BR suseconds_t

shall be a signed integer type capable of storing values at least in

the range [\(mi1,\ 1\|000\|000].

.P

The implementation shall support one or more programming environments

in which the widths of

.BR blksize_t ,

.BR pid_t ,

.BR size_t ,

.BR ssize_t ,

and

.BR suseconds_t

are no greater than the width of type

.BR long .

The names of these programming environments can be obtained using the

\fIconfstr\fR()

function or the

.IR getconf

utility.

.P

There are no defined comparison or assignment operators for the

following types:

.P

.nf

.BR pthread_attr_t

.BR pthread_barrier_t

.BR pthread_barrierattr_t

.BR pthread_cond_t

.BR pthread_condattr_t

.BR pthread_mutex_t

.BR pthread_mutexattr_t

.BR pthread_rwlock_t

.BR pthread_rwlockattr_t

.BR pthread_spinlock_t

.BR trace_attr_t

.fi

.LP

.IR "The following sections are informative."

.SH "APPLICATION USAGE"

None.

.SH RATIONALE

None.

.SH "FUTURE DIRECTIONS"

None.

.SH "SEE ALSO"

.IR "\fB<time.h>\fP"

.P

The System Interfaces volume of POSIX.1\(hy2008,

.IR "\fIconfstr\fR\^(\|)"

.P

The Shell and Utilities volume of POSIX.1\(hy2008,

.IR "\fIgetconf\fR\^"

.SH COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form

from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology

-- Portable Operating System Interface (POSIX), The Open Group Base

Specifications Issue 7, Copyright (C) 2013 by the Institute of

Electrical and Electronics Engineers, Inc and The Open Group.

(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html .

Any typographical or formatting errors that appear

in this page are most likely

to have been introduced during the conversion of the source files to

man page format. To report such errors, see

https://www.kernel.org/doc/man-pages/reporting_bugs.html .