xref: /freebsd/lib/libc/string/strxfrm.3 (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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32.Dd June 4, 1993
33.Dt STRXFRM 3
34.Os
35.Sh NAME
36.Nm strxfrm
37.Nd transform a string under locale
38.Sh LIBRARY
39.Lb libc
40.Sh SYNOPSIS
41.In string.h
42.Ft size_t
43.Fn strxfrm "char * restrict dst" "const char * restrict src" "size_t n"
44.Ft size_t
45.Fn strxfrm_l "char * restrict dst" "const char *restrict src" "size_t n" "locale_t loc"
46.Sh DESCRIPTION
47The
48.Fn strxfrm
49function transforms a null-terminated string pointed to by
50.Fa src
51according to the current locale collation if any,
52then copies the transformed string
53into
54.Fa dst .
55Not more than
56.Fa n
57characters are copied into
58.Fa dst ,
59including the terminating null character added.
60If
61.Fa n
62is set to 0
63(it helps to determine an actual size needed
64for transformation),
65.Fa dst
66is permitted to be a NULL pointer.
67.Pp
68Comparing two strings using
69.Fn strcmp
70after
71.Fn strxfrm
72is equal to comparing
73two original strings with
74.Fn strcoll .
75.Pp
76.Fn strxfrm_l
77does the same, however takes an explicit locale rather than the global
78locale.
79.Sh RETURN VALUES
80Upon successful completion,
81.Fn strxfrm
82and
83.Fn strxfrm_l
84return the length of the transformed string not including
85the terminating null character.
86If this value is
87.Fa n
88or more, the contents of
89.Fa dst
90are indeterminate.
91.Sh SEE ALSO
92.Xr setlocale 3 ,
93.Xr strcmp 3 ,
94.Xr strcoll 3 ,
95.Xr wcsxfrm 3
96.Sh STANDARDS
97The
98.Fn strxfrm
99function
100conforms to
101.St -isoC .
102The
103.Fn strxfrm_l
104function conforms to
105.St -p1003.1-2008 .
106