Tribblix: manual page: strxfrm.3c

STRXFRM(3C) Standard C Library Functions STRXFRM(3C)

NAME

strxfrm, strxfrm_l - string transformation

SYNOPSIS

#include <string.h>

size_t strxfrm(char *restrict s1, const char *restrict s2, size_t n);

size_t strxfrm_l(char *restrict s1, const char *restrict s2, size_t n,
locale_t loc);

DESCRIPTION

The strxfrm() function transforms the string pointed to by s2 and
places the resulting string into the array pointed to by s1. The
transformation is such that if strcmp(3C) is applied to two
transformed strings, it returns a value greater than, equal to or
less than 0, corresponding 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.

The strxfrm_l() functions behaves identically to the function
strxfrm(), except instead of operating in the current locale it
operates in the locale specified by the argument loc.

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
information in the 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
transformation.

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/LC_COLLATE/*
collation database for locale

ATTRIBUTES