xref: /freebsd/lib/libc/string/strxfrm.3 (revision 7f3dea244c40159a41ab22da77a434d7c5b5e85a)
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36.\"     @(#)strxfrm.3	8.1 (Berkeley) 6/4/93
37.\" $FreeBSD$
38.\"
39.Dd June 4, 1993
40.Dt STRXFRM 3
41.Os
42.Sh NAME
43.Nm strxfrm
44.Nd transform a string under locale
45.Sh SYNOPSIS
46.Fd #include <string.h>
47.Ft size_t
48.Fn strxfrm "char *dst" "const char *src" "size_t n"
49.Sh DESCRIPTION
50The
51.Fn strxfrm
52function transforms a null-terminated string pointed to by
53.Fa src
54according to the current locale collation if any,
55then copies the transformed string
56into
57.Fa dst .
58Not more than
59.Fa n
60characters are copied into
61.Fa dst ,
62including the terminating null character added.
63If
64.Fa n
65is set to 0
66(it helps to determine an actual size needed
67for transformation),
68.Fa dst
69is permitted to be a NULL pointer.
70.Pp
71Comparing two strings using
72.Fn strcmp
73after
74.Fn strxfrm
75is equal to comparing
76two original strings with
77.Fn strcoll .
78.Sh RETURN VALUES
79Upon successful completion,
80.Fn strxfrm
81returns the length of the transformed string not including
82the terminating null character. If this value is
83.Fa n
84or more, the contents of
85.Fa dst
86are indeterminate.
87.Sh SEE ALSO
88.Xr setlocale 3 ,
89.Xr strcmp 3 ,
90.Xr strcoll 3
91.Sh STANDARDS
92The
93.Fn strxfrm
94function
95conforms to
96.St -ansiC .
97