1STRCASECMP(3P)             POSIX Programmer's Manual            STRCASECMP(3P)
2
3
4

PROLOG

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
11

NAME

13       strcasecmp, strcasecmp_l, strncasecmp, strncasecmp_l — case-insensitive
14       string comparisons
15

SYNOPSIS

17       #include <strings.h>
18
19       int strcasecmp(const char *s1, const char *s2);
20       int strcasecmp_l(const char *s1, const char *s2,
21           locale_t locale);
22       int strncasecmp(const char *s1, const char *s2, size_t n);
23       int strncasecmp_l(const char *s1, const char *s2,
24           size_t n, locale_t locale);
25

DESCRIPTION

27       The  strcasecmp()  and  strcasecmp_l()  functions  shall compare, while
28       ignoring differences in case, the string pointed to by s1 to the string
29       pointed  to  by  s2.   The  strncasecmp() and strncasecmp_l() functions
30       shall compare, while ignoring differences in  case,  not  more  than  n
31       bytes from the string pointed to by s1 to the string pointed to by s2.
32
33       The  strcasecmp() and strncasecmp() functions use the current locale to
34       determine the case of the characters.
35
36       The strcasecmp_l() and strncasecmp_l() functions use the locale  repre‐
37       sented by locale to determine the case of the characters.
38
39       When  the  LC_CTYPE category of the locale being used is from the POSIX
40       locale, these functions shall behave as if the strings  had  been  con‐
41       verted  to  lowercase  and then a byte comparison performed. Otherwise,
42       the results are unspecified.
43
44       The behavior is undefined if the locale argument to  strcasecmp_l()  or
45       strncasecmp_l() is the special locale object LC_GLOBAL_LOCALE or is not
46       a valid locale object handle.
47

RETURN VALUE

49       Upon completion, strcasecmp() and strcasecmp_l() shall return an  inte‐
50       ger greater than, equal to, or less than 0, if the string pointed to by
51       s1 is, ignoring case, greater than, equal to, or less than  the  string
52       pointed to by s2, respectively.
53
54       Upon  successful  completion,  strncasecmp()  and strncasecmp_l() shall
55       return an integer greater than, equal to, or less than 0, if the possi‐
56       bly  null-terminated  array pointed to by s1 is, ignoring case, greater
57       than, equal to, or less than the possibly null-terminated array pointed
58       to by s2, respectively.
59

ERRORS

61       No errors are defined.
62
63       The following sections are informative.
64

EXAMPLES

66       None.
67

APPLICATION USAGE

69       None.
70

RATIONALE

72       None.
73

FUTURE DIRECTIONS

75       None.
76

SEE ALSO

78       wcscasecmp()
79
80       The Base Definitions volume of POSIX.1‐2008, <strings.h>
81
83       Portions  of  this text are reprinted and reproduced in electronic form
84       from IEEE Std 1003.1, 2013 Edition, Standard for Information Technology
85       --  Portable  Operating  System  Interface (POSIX), The Open Group Base
86       Specifications Issue 7, Copyright (C) 2013 by the Institute of Electri‐
87       cal  and  Electronics  Engineers,  Inc  and  The  Open Group.  (This is
88       POSIX.1-2008 with the 2013 Technical Corrigendum  1  applied.)  In  the
89       event of any discrepancy between this version and the original IEEE and
90       The Open Group Standard, the original IEEE and The Open Group  Standard
91       is  the  referee document. The original Standard can be obtained online
92       at http://www.unix.org/online.html .
93
94       Any typographical or formatting errors that appear  in  this  page  are
95       most likely to have been introduced during the conversion of the source
96       files to man page format. To report such errors,  see  https://www.ker
97       nel.org/doc/man-pages/reporting_bugs.html .
98
99
100
101IEEE/The Open Group                  2013                       STRCASECMP(3P)
Impressum