strxfrm(3c) [sunos man page]
strxfrm(3C) Standard C Library Functions strxfrm(3C) 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 transforms the string pointed to by s2 and places the resulting string into the array pointed to by s1. The trans- formation is such that if strcmp(3C) is applied to two transformed strings, it returns a value greater than, equal to or less than 0, cor- responding to the result of strcoll(3C) 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 does 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(), then check errno. RETURN VALUES
Upon successful completion, strxfrm() returns 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 indeterminate. On error, strxfrm() may set errno but no return value is reserved to indicate the error. USAGE
The transformation function is such that two transformed strings can be ordered by strcmp(3C) as appropriate to collating sequence informa- tion in the program's 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 trans- formation. EXAMPLES
Example 1: A sample of using the strxfm() function. The value of the following expression is the size of the array needed to hold the transformation of the string pointed to by s. 1 + strxfrm(NULL, s, 0); FILES
/usr/lib/locale/locale/locale.so.* LC_COLLATE database for locale ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |CSI |Enabled | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe with exceptions | +-----------------------------+-----------------------------+ The strxfrm() function can be used safely in a multithreaded application, as long as setlocale(3C) is not being called to change the locale. SEE ALSO
localedef(1), setlocale(3C), strcmp(3C), strcoll(3C), wscoll(3C), attributes(5), environ(5), standards(5) SunOS 5.10 10 Dec 2003 strxfrm(3C)
Check Out this Related Man Page
strxfrm(3) Library Functions Manual strxfrm(3) NAME
strxfrm - Transforms string for collation in current locale LIBRARY
Standard C Library (libc.so, libc.a) SYNOPSIS
#include <string.h> size_t strxfrm( char *s1, const char *s2, size_t n); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: strxfrm(): XPG4, XPG4-UNIX Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
Specifies the destination string. Specifies the string to be transformed. Specifies the maximum number of bytes to store in the trans- formed string. DESCRIPTION
The strxfrm() function transforms the string pointed to by the s2 parameter into an internal form suitable for collation and places the result in the address specified by s1. This transformation is performed as appropriate to the LC_COLLATE category of the current locale. When the strcmp() function is applied to two transformed strings, a value greater than, equal to, or less than 0 (zero) is returned. The returned value corresponds to the same value that is returned when the strcoll() function is applied to the same two original transformed strings. The transformed string can be longer than the original string. No more than n characters are placed in the location pointed to by the s1 parameter, including the terminating null character. When n is 0 (zero), the s1 parameter can be a null pointer. When operating on overlapping strings, the behavior of this function is unreliable. NOTES
If you are doing multiple comparisons using the same set of text strings, the strxfrm() transformation function in conjunction with the strcmp() function may be more efficient than using the strcoll() collation function because the string is transformed based on the locale tables only once. However, the transformation function must convert all characters in the string for each level of a multi-level colla- tion. In comparison, the collation function stops comparing characters at the first inequality. These efficiency tradeoffs make the most efficient method for a specific application dependent on both the number of repeated comparisons for each string and the contents of each string. RETURN VALUES
Upon successful completion, the strxfrm() function returns the number of bytes required to store the transformed string (not including the terminating null byte). If this is greater than or equal to the value of the n parameter, which specifies the maximum number of bytes that can be stored in s1, the contents of s1 are indeterminate. ERRORS
If the following condition occurs, the strxfrm() function sets errno to the corresponding value. The s2 parameter contains codes outside the domain of the collating sequence defined by the current locale. RELATED INFORMATION
Functions: setlocale(3), strcoll(3), string(3)/strcmp(3), wcsxfrm(3) Standards: standards(5) delim off strxfrm(3)