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



PROLOG
       This  manual  page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (con-
       sult the corresponding Linux manual page for details of Linux behavior), or the  interface  may  not  be  implemented  on
       Linux.

NAME
       strcoll - string comparison using collating information

SYNOPSIS
       #include <string.h>

       int strcoll(const char *s1, const char *s2);


DESCRIPTION
       The  strcoll()  function  shall  compare  the string pointed to by s1 to the string pointed to by s2, both interpreted as
       appropriate to the LC_COLLATE category of the current locale.

       The strcoll() function 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 strcoll(), then check errno.

RETURN VALUE
       Upon  successful  completion,  strcoll()  shall  return  an  integer greater than, equal to, or less than 0, according to
       whether the string pointed to by s1 is greater than, equal to, or less than the string pointed to by  s2  when  both  are
       interpreted  as appropriate to the current locale.  On error, strcoll() may set errno, but no return value is reserved to
       indicate an error.

ERRORS
       The strcoll() function may fail if:

       EINVAL The s1 or s2 arguments contain characters outside the domain of the collating sequence.


       The following sections are informative.

EXAMPLES
   Comparing Nodes
       The following example uses an application-defined function, node_compare(), to compare two nodes based on an alphabetical
       ordering of the string field.


              #include <string.h>
              ...
              struct node { /* These are stored in the table. */
                  char *string;
                  int length;
              };
              ...
              int node_compare(const void *node1, const void *node2)
              {
                  return strcoll(((const struct node *)node1)->string,
                      ((const struct node *)node2)->string);
              }
              ...

APPLICATION USAGE
       The strxfrm() and strcmp() functions should be used for sorting large lists.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       strcmp(), strxfrm(), 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,  Copy-
       right (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.open-
       group.org/unix/online.html .



IEEE/The Open Group                                           2003                                                   STRCOLL(3P)