4.1cBSD/usr/man/man3/qsort.3f

.TH QSORT 3F "19 January 1983"
.SH NAME
qsort \- quick sort
.SH SYNOPSIS
.B subroutine qsort (array, len, isize, compar)
.br
.B external compar
.br
.B integer*2 compar
.SH DESCRIPTION
One dimensional
.I array
contains the elements to be sorted.
.I len
is the number of elements in the array.
.I isize
is the size of an element, typically -
.sp 1
.in +5
4 for
.B integer
and
.B real
.br
8 for
.B "double precision"
or
.B complex
.br
16 for
.B "double complex"
.br
(length of character object) for
.B character
arrays
.in -5
.sp 1
.I Compar
is the name of a user supplied integer*2 function
that will determine the sorting order.
This function will be called with 2 arguments that will be elements of
.I array.
The function must return -
.sp 1
.in +5
negative if arg 1 is precedent to arg 2
.br
zero if arg 1 is equivalent to arg 2
.br
positive if arg 1 is subsequent to arg 2
.in -5
.sp 1
On return, the elements of
.I array
will be sorted.
.SH FILES
.ie \nM /usr/ucb/lib/libU77.a
.el /usr/lib/libU77.a
.SH "SEE ALSO"
qsort(3)