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



PPRROOLLOOGG
       This manual page is part of the POSIX Programmer's Manual.  The OS
       implementation of this interface may differ (consult the corresponding
       OS manual page for details of OS behavior), or the interface may not be
       implemented on OS.


NNAAMMEE
       strcoll, strcoll_l -- string comparison using collating information

SSYYNNOOPPSSIISS
       #include <string.h>

       int strcoll(const char *_s_1, const char *_s_2);
       int strcoll_l(const char *_s_1, const char *_s_2,
           locale_t _l_o_c_a_l_e);

DDEESSCCRRIIPPTTIIOONN
       For _s_t_r_c_o_l_l(): 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 _s_t_r_c_o_l_l() and _s_t_r_c_o_l_l___l() functions shall compare the string
       pointed to by _s_1 to the string pointed to by _s_2, both interpreted as
       appropriate to the _L_C___C_O_L_L_A_T_E category of the current locale, or of the
       locale represented by _l_o_c_a_l_e, respectively.

       The _s_t_r_c_o_l_l() and _s_t_r_c_o_l_l___l() functions shall not change the setting of
       _e_r_r_n_o if successful.

       Since no return value is reserved to indicate an error, an application
       wishing to check for error situations should set _e_r_r_n_o to 0, then call
       _s_t_r_c_o_l_l(), or _s_t_r_c_o_l_l___l() then check _e_r_r_n_o.

       The behavior is undefined if the _l_o_c_a_l_e argument to _s_t_r_c_o_l_l___l() is the
       special locale object LC_GLOBAL_LOCALE or is not a valid locale object
       handle.

RREETTUURRNN VVAALLUUEE
       Upon successful completion, _s_t_r_c_o_l_l() shall return an integer greater
       than, equal to, or less than 0, according to whether the string pointed
       to by _s_1 is greater than, equal to, or less than the string pointed to
       by _s_2 when both are interpreted as appropriate to the current locale.
       On error, _s_t_r_c_o_l_l() may set _e_r_r_n_o, but no return value is reserved to
       indicate an error.

       Upon successful completion, _s_t_r_c_o_l_l___l() shall return an integer greater
       than, equal to, or less than 0, according to whether the string pointed
       to by _s_1 is greater than, equal to, or less than the string pointed to
       by _s_2 when both are interpreted as appropriate to the locale
       represented by _l_o_c_a_l_e.  On error, _s_t_r_c_o_l_l___l() may set _e_r_r_n_o, but no
       return value is reserved to indicate an error.

EERRRROORRSS
       These functions may fail if:

       EEIINNVVAALL The _s_1 or _s_2 arguments contain characters outside the domain of
              the collating sequence.

       _T_h_e _f_o_l_l_o_w_i_n_g _s_e_c_t_i_o_n_s _a_r_e _i_n_f_o_r_m_a_t_i_v_e_.

EEXXAAMMPPLLEESS
   CCoommppaarriinngg NNooddeess
       The following example uses an application-defined function,
       _n_o_d_e___c_o_m_p_a_r_e(), to compare two nodes based on an alphabetical ordering
       of the _s_t_r_i_n_g field.

           ##iinncclluuddee <<ssttrriinngg..hh>>
           ......
           ssttrruucctt nnooddee {{ //** TThheessee aarree ssttoorreedd iinn tthhee ttaabbllee.. **//
               cchhaarr **ssttrriinngg;;
               iinntt lleennggtthh;;
           }};;
           ......
           iinntt nnooddee__ccoommppaarree((ccoonnsstt vvooiidd **nnooddee11,, ccoonnsstt vvooiidd **nnooddee22))
           {{
               rreettuurrnn ssttrrccoollll((((((ccoonnsstt ssttrruucctt nnooddee **))nnooddee11))-->>ssttrriinngg,,
                   ((((ccoonnsstt ssttrruucctt nnooddee **))nnooddee22))-->>ssttrriinngg));;
           }}
           ......

AAPPPPLLIICCAATTIIOONN UUSSAAGGEE
       The _s_t_r_x_f_r_m() and _s_t_r_c_m_p() functions should be used for sorting large
       lists.

RRAATTIIOONNAALLEE
       None.

FFUUTTUURREE DDIIRREECCTTIIOONNSS
       None.

SSEEEE AALLSSOO
       _a_l_p_h_a_s_o_r_t(), _s_t_r_c_m_p(), _s_t_r_x_f_r_m()

       The Base Definitions volume of POSIX.1-2008, <<ssttrriinngg..hh>>

CCOOPPYYRRIIGGHHTT
       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
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .



IEEE/The Open Group                  2013                           STRCOLL(3)
