wsregexp(3W)
wsregexp: wsrecompile, wsrestep, wsrematch, wsreerr - Wide character based regular expression compile and match routines
As shipped in IRIX 6.5.5. Unchanged since IRIX 6.5.
NAME wsregexp: wsrecompile, wsrestep, wsrematch, wsreerr - Wide character based regular expression compile and match routines SYNOPSIS #include <wsregexp.h> #include <widec.h> long wsrecompile(struct rexdata *prex, long *expbuf, long *endbuf, wchar_t eof); int wsrestep(struct rexdata *prex, wchar_t *wstr, long *expbuf); int wsrematch(struct rexdata *prex, wchar_t *wstr, long *expbuf); char *wsreerr(int err); DESCRIPTION These functions are general purpose internationalized regular expression matching routines to be used in programs that perform regular expression matching. These functions are defined by the wsregexp.h header file. The function wsrecompile takes as input an internationalized regular expression as defined below (apart from the normal regular expressions as defined by regexp) and produces a compiled expression that can be used with wsrestep or wsrematch. struct rexdata { short sed; /* flag for sed */ wchar_t *str; /* regular expression */ int err; /* returned error code, 0 = no error */ wchar_t *loc1; wchar_t *loc2; int circf; ... }; The first parameter, prex, is a pointer to the specification of the regular expression. prex->sed should be non-zero if sed style delimiter syntax is to be adopted. prex->str should point to the regular expression that needs to be compiled. The regular expression string should be in wide character format. prex->err indicated any error during the compilation and use of this regular expression. expbuf points to the place where the compiled regular expression will be placed. endbuf points to the first long after the space where the compiled regular expression may be placed. (endbuf-expbuf) should be large enough for the compiled regular expression to fit. eof is the wide character which marks the end of the regular expression. This character is usually a / (slash). If wsrecompile was successful, it returns the pointer to the end of the regular expression, endbuf. Otherwise, 0 is returned and the error code is set in prex->err. The functions wsrestep and wsrematch do pattern matching given a null terminated wide character string wstr and a compiled regular expression expbuf as input. expbuf for these functions should be the compiled regular expression which was obtained by a call to the function wsrecompile. The function wsrestep returns non-zero if some substring of wstr matches the regular expression in expbuf and zero if there is no match. The function wsrematch returns non-zero if a substring of wstr starting from the beginning matches the regular expression in expbuf and zero if there is no match. If there is a match, prex->loc1 and prex->loc2 are set. prex->loc1 points to the first wide character that matched the regular expression; prex->loc2 points to the wide character after the last wide character that matches the regular expression. Thus if the regular expression matches the entire input string, prex->loc1 will point to the first wide character of wstr and prex->loc2 will point to the null at the end of wstr. wsrestep uses the variable circf of struct rexdata which is set by wsrecompile if the regular expression begins with ^ (caret). If this is set then wsrestep will try to match the regular expression to the beginning of the string only. If more than one regular expression is to be compiled before the first is executed, the value of prex->circf should be saved for each compiled expression and should be set to that saved value before each call to wsrestep. wsreerr returns the error message corresponding to the error code in the language of the current locale. The error code err should be one returned by the wsregexp functions in the err variable of struct rexdata. The internationalized regular expressions available for use with the wsregexp functions are constructed as follows: Expression Meaning c the character c where c is not a special character. [[:class:]] class is any character type as defined by the LC_TYPE locale catagory. class can be one of the following alpha a letter upper an upper-case letter lower a lower-case letter digit a decimal digit xdigit a hexadecimal digit alnum an alphanumeric character space any whitespace character punct a punctuation character print a printable character graph a character that has a visible representation cntrl a control character [[=c=]] An equivalence class, or, any collation element defined as having the same relative order in the current collation sequence as c. As an example, if A and a belong to the same equivalence class, then both [[=A=]b]] and [[=a=]b]] are equivalent to [Aab]. [[.cc.]] This represents a multi-character collating symbol. Multi- character collating elements must be represented as collating symbols to distinguish them from single-character collating elements. As an example, if the string ab is a valid collating element, then [[.ab.]] will be treated as an element and will match the same string of characters, while ab will match the list of characters a and b. If the multi- character collating symbol is not a valid collating element in the current collating sequence definition, the symbol will be treated as an invalid expression. [[c-c]] Any collation element in the character expression range c-c, where c can identify a collating symbol or an equivalence class. If the character - (hyphen) appears immediately after an opening square bracker, e.g. [-c], or immediately prior to a closing square bracket, e.g. [c-], it has no special meaning. Immediately following an opening square bracket ^ means the complement of, e.g. [^c]. Otherwise, it has no special meaning. Within square brackets, a . that is not part of a [[.cc.]] sequence, or a : that is not part of a [[:class:]] sequence, matches itself. SEE ALSO regexp(5) DIAGNOSTICS Errors are: ERR_NORMBR no remembered search string ERR_REOVFLOW regexp overflow This happens when wsrecompile cant fit the compiled regular expression in (endbuf- expbuf). ERR_BRA ( ) imbalance ERR_DELIM illegal or missing delimiter. ERR_NBR bad number in { } ERR_2MNBR more than 2 numbers given in { } ERR_DIGIT digit out of range ERR_2MLBRA too many ( ERR_RANGE range number too large ERR_MISSB } expected after \ ERR_BADRNG first number exceeds second in { }. ERR_SIMBAL [ ] imbalance. ERR_SYNTAX illegal regular expression ERR_ILLCLASS illegal [:class:] ERR_EQUIL illegal [=class=] ERR_COLL illegal [.cc.] EXAMPLE The following is an example of how the regular expression macros and calls might be defined by an application program: #include <wsregexp.h> #include <widec.h> . . . struct rexdata rex; long expbuf [BUFSIZ]; /* Buffer for the compiled RE */ /* Define a RE to identify a capitalized word */ char *regexp = "[[:space:]][[:upper:]]"; wchar_t wregexp [512]; wchar_t weof; /* The end of regular expression */ char eof = '\0'; wchar_t linebuf [BUFSIZ]; /* Buffer for the input string */ . . . (void) mbstowcs(wregexp, regexp, strlen(regexp)+1); (void) mbtowc(&weof, &eof, 1); rex.str = wregexp; rex.sed = 0; rex.err = 0; if (!wsrecompile(&rex, expbuf, &expbuf[BUFSIZ], weof)) fprintf(stderr, "%s\n", wsreerr(rex.err)); . . . if (wsrestep(&rex, linebuf, expbuf)) succeed;