.\" Copyright 2020, Michael Kerrisk <mtk.manpages@gmail.com>
.\" Copyright, the authors of the Linux man-pages project
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.TH ptrdiff_t 3type 2026-02-08 "Linux man-pages 6.17"
.SH NAME
ptrdiff_t \- count of elements or array index
.SH LIBRARY
Standard C library
.RI ( libc )
.SH SYNOPSIS
.nf
.B #include <stddef.h>
.P
.BR typedef " /* ... */  " ptrdiff_t;
.fi
.SH DESCRIPTION
Used for a count of elements, or an array index.
It is the result of subtracting two pointers.
It is a signed integer type
capable of storing values in the range
.RB [ PTRDIFF_MIN ,
.BR PTRDIFF_MAX ].
.P
The length modifier for
.I ptrdiff_t
for the
.BR printf (3)
and the
.BR scanf (3)
families of functions is
.BR t ,
resulting commonly in
.B %td
or
.B %ti
for printing
.I ptrdiff_t
values.
.SH STANDARDS
C11, POSIX.1-2024.
.SH HISTORY
C89,
SUSv1,
POSIX.1-2001.
.SH SEE ALSO
.BR size_t (3type)