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STRXFRM(3P)                POSIX Programmer's Manual               STRXFRM(3P)

PROLOG
       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.
NAME
       strxfrm - string transformation
SYNOPSIS
       #include <string.h>
       size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n);

DESCRIPTION
       The strxfrm() function shall transform the string pointed to by s2  and
       place  the resulting string into the array pointed to by s1. The trans-
       formation 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() applied  to  the  same  two
       original  strings.  No  more than n bytes are placed into the resulting
       array pointed to by s1, including the terminating null byte. 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() function shall not change the setting of  errno  if  suc-
       cessful.
       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(), then check errno.
RETURN VALUE
       Upon  successful  completion,  strxfrm() shall return the length of the
       transformed string (not including the terminating null  byte).  If  the
       value returned is n or more, the contents of the array pointed to by s1
       are unspecified.
       On error, strxfrm() may set errno but no return value  is  reserved  to
       indicate an error.
ERRORS
       The strxfrm() function may fail if:
       EINVAL The  string  pointed  to  by the s2 argument contains characters
              outside the domain of the collating sequence.

       The following sections are informative.
EXAMPLES
       None.
APPLICATION USAGE
       The transformation function is such that two transformed strings can be
       ordered by strcmp() as appropriate to collating sequence information in
       the program's locale (category LC_COLLATE ).
       The fact that when n is 0 s1 is permitted to be a null pointer is  use-
       ful to determine the size of the s1 array prior to making the transfor-
       mation.
RATIONALE
       None.
FUTURE DIRECTIONS
       None.
SEE ALSO
       strcmp(),    strcoll(),    the    Base    Definitions     volume     of
       IEEE Std 1003.1-2001, <string.h>
COPYRIGHT
       Portions  of  this text are reprinted and reproduced in electronic form
       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
       Specifications Issue 6, Copyright (C) 2001-2003  by  the  Institute  of
       Electrical  and  Electronics  Engineers, Inc and The Open Group. 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.opengroup.org/unix/online.html .

IEEE/The Open Group                  2003                          STRXFRM(3P)