1STRXFRM(3P) POSIX Programmer's Manual STRXFRM(3P)
2
6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
10
12 strxfrm, strxfrm_l — string transformation
13
15 #include <string.h>
16 size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n);
18 size_t strxfrm_l(char *restrict s1, const char *restrict s2,
19 size_t n, locale_t locale);
20
22 For strxfrm(): The functionality described on this reference page is
23 aligned with the ISO C standard. Any conflict between the requirements
24 described here and the ISO C standard is unintentional. This volume of
25 POSIX.1‐2017 defers to the ISO C standard.
26 The strxfrm() and strxfrm_l() functions shall transform the string
28 pointed to by s2 and place the resulting string into the array pointed
29 to by s1. The transformation is such that if strcmp() is applied to
30 two transformed strings, it shall return a value greater than, equal
31 to, or less than 0, corresponding to the result of strcoll() or str‐
32 coll_l(), respectively, applied to the same two original strings with
33 the same locale. No more than n bytes are placed into the resulting
34 array pointed to by s1, including the terminating NUL character. If n
35 is 0, s1 is permitted to be a null pointer. If copying takes place
36 between objects that overlap, the behavior is undefined.
37 The strxfrm() and strxfrm_l() functions shall not change the setting of
39 errno if successful.
40 Since no return value is reserved to indicate an error, an application
42 wishing to check for error situations should set errno to 0, then call
43 strxfrm() or strxfrm_l(), then check errno.
44 The behavior is undefined if the locale argument to strxfrm_l() is the
46 special locale object LC_GLOBAL_LOCALE or is not a valid locale object
47 handle.
48
50 Upon successful completion, strxfrm() and strxfrm_l() shall return the
51 length of the transformed string (not including the terminating NUL
52 character). If the value returned is n or more, the contents of the
53 array pointed to by s1 are unspecified.
54 On error, strxfrm() and strxfrm_l() may set errno but no return value
56 is reserved to indicate an error.
57
59 These functions may fail if:
60 EINVAL The string pointed to by the s2 argument contains characters
62 outside the domain of the collating sequence.
63 The following sections are informative.
65
67 None.
68
70 The transformation function is such that two transformed strings can be
71 ordered by strcmp() as appropriate to collating sequence information in
72 the current locale (category LC_COLLATE).
73 The fact that when n is 0 s1 is permitted to be a null pointer is use‐
75 ful to determine the size of the s1 array prior to making the transfor‐
76 mation.
77
79 None.
80
82 None.
83
85 strcmp(), strcoll()
86 The Base Definitions volume of POSIX.1‐2017, <string.h>
88
90 Portions of this text are reprinted and reproduced in electronic form
91 from IEEE Std 1003.1-2017, Standard for Information Technology -- Por‐
92 table Operating System Interface (POSIX), The Open Group Base Specifi‐
93 cations Issue 7, 2018 Edition, Copyright (C) 2018 by the Institute of
94 Electrical and Electronics Engineers, Inc and The Open Group. In the
95 event of any discrepancy between this version and the original IEEE and
96 The Open Group Standard, the original IEEE and The Open Group Standard
97 is the referee document. The original Standard can be obtained online
98 at http://www.opengroup.org/unix/online.html .
99 Any typographical or formatting errors that appear in this page are
101 most likely to have been introduced during the conversion of the source
102 files to man page format. To report such errors, see https://www.ker‐
103 nel.org/doc/man-pages/reporting_bugs.html .
104IEEE/The Open Group 2017 STRXFRM(3P)