This manual page is part of the POSIX Programmer's Manual. The Linux
implementation of this interface may differ (consult the
corresponding Linux manual page for details of Linux behavior), or
the interface may not be implemented on Linux.
For strxfrm(): The functionality described on this reference page is
aligned with the ISO C standard. Any conflict between the
requirements described here and the ISO C standard is unintentional.
This volume of POSIX.1‐2008 defers to the ISO C standard.
The strxfrm() and strxfrm_l() functions shall transform the string
pointed to by s2 and place the resulting string into the array
pointed to by s1. The transformation is such that if strcmp() is
applied to two transformed strings, it shall return a value greater
than, equal to, or less than 0, corresponding to the result of
strcoll() or strcoll_l(), respectively, applied to the same two
original strings with the same locale. No more than n bytes are
placed into the resulting array pointed to by s1, including the
terminating NUL character. If n is 0, s1 is permitted to be a null
pointer. If copying takes place between objects that overlap, the
behavior is undefined.
The strxfrm() and strxfrm_l() functions shall not change the setting
of errno if successful.
Since no return value is reserved to indicate an error, an
application wishing to check for error situations should set errno to
0, then call strxfrm() or strxfrm_l(), then check errno.
The behavior is undefined if the locale argument to strxfrm_l() is
the special locale object LC_GLOBAL_LOCALE or is not a valid locale
Upon successful completion, strxfrm() and strxfrm_l() shall return
the length of the transformed string (not including the terminating
NUL character). If the value returned is n or more, the contents of
the array pointed to by s1 are unspecified.
On error, strxfrm() and strxfrm_l() may set errno but no return value
is reserved to indicate an error.
The transformation function is such that two transformed strings can
be ordered by strcmp() as appropriate to collating sequence
information in the current locale (category LC_COLLATE).
The fact that when n is 0 s1 is permitted to be a null pointer is
useful to determine the size of the s1 array prior to making the
Portions of this text are reprinted and reproduced in electronic form
from IEEE Std 1003.1, 2013 Edition, Standard for Information
Technology -- Portable Operating System Interface (POSIX), The Open
Group Base Specifications Issue 7, Copyright (C) 2013 by the
Institute of Electrical and Electronics Engineers, Inc and The Open
Group. (This is POSIX.1-2008 with the 2013 Technical Corrigendum 1
applied.) In the event of any discrepancy between this version and
the original IEEE and The Open Group Standard, the original IEEE and
The Open Group Standard is the referee document. The original
Standard can be obtained online at http://www.unix.org/online.html .
Any typographical or formatting errors that appear in this page are
most likely to have been introduced during the conversion of the
source files to man page format. To report such errors, see
IEEE/The Open Group 2013 STRXFRM(3P)