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diff --git a/sys/fmtio/strmatch.x b/sys/fmtio/strmatch.x
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+# Copyright(c) 1986 Association of Universities for Research in Astronomy Inc.
+
+include	<ctype.h>
+include <pattern.h>
+
+.help strmatch, gstrmatch
+.nf ________________________________________________________________________
+STRMATCH -- Find the first occurrence of the string A in the string B.
+If not found, return zero, else return the index of the first character
+following the matched substring.
+
+GSTRMATCH -- More general version of strmatch.  The indices of the
+first and last characters matched are returned as arguments.  The function
+value is the same as for STRMATCH.
+
+STRMATCH recognizes the metacharacters BOL, EOL, ANY, WHITESPACE, IGNORECASE,
+and MATCHCASE (BOL and EOL are special only as the first and last chars
+in the pattern).  The null pattern matches any string.  Metacharacters
+can be escaped.
+.endhelp ___________________________________________________________________
+
+
+# STRMATCH -- Search string STR for pattern PAT.  Return the index of the
+# next character following the matched substring, or 0.
+
+int procedure strmatch (str, pat)
+
+char	pat[ARB], str[ARB]
+int	first_char, last_char
+int	gstrmatch()
+
+begin
+	return (gstrmatch (str, pat, first_char, last_char))
+end
+
+
+# GSTRMATCH -- Generalized string match.  Returns the indices of the first and
+# last characters in the matched substring if a match occurs.
+
+int procedure gstrmatch (str, pat, first_char, last_char)
+
+char	pat[ARB], str[ARB]
+int	first_char, last_char
+bool	ignore_case, bolflag
+char	ch, pch
+int	i, ip, initial_pp, pp
+
+begin
+	ignore_case = false
+	bolflag = false
+	first_char = 1
+	initial_pp = 1
+
+	if (pat[1] == CH_BOL) {			# match at beginning of line?
+	    bolflag = true
+	    initial_pp = 2
+	}
+	    
+	# Try to match pattern starting at each character offset in string.
+	do ip = 1, ARB {
+	    if (str[ip] == EOS)
+		break
+	    i = ip
+
+	    # Compare pattern to string str[ip].
+	    for (pp=initial_pp;  pat[pp] != EOS;  pp=pp+1) {
+		switch (pat[pp]) {
+		case CH_WHITESPACE:
+		    while (IS_WHITE (str[i]))
+			i = i + 1
+		case CH_ANY:
+		    if (str[i] != '\n')
+			i = i + 1
+		case CH_IGNORECASE:
+		    ignore_case = true
+		case CH_MATCHCASE:
+		    ignore_case = false
+		
+		default:
+		    pch = pat[pp]
+		    if (pch == CH_ESCAPE && pat[pp+1] != EOS) {
+			pp = pp + 1
+			pch = pat[pp]
+		    } else if (pch == CH_EOL)
+		        if (pat[pp+1] == EOS && (str[i]=='\n' || str[i]==EOS)) {
+			    first_char = ip
+			    last_char = i
+			    if (str[i] == EOS)
+				last_char = last_char - 1
+			    return (last_char + 1)
+			}
+
+		    ch = str[i]
+		    i = i + 1
+
+		    # Compare ordinary characters.  The comparison is trivial
+		    # unless case insensitivity is required.
+
+		    if (ignore_case) {
+	                if (IS_UPPER (ch)) {
+			    if (IS_UPPER (pch)) {
+				if (pch != ch)
+				    break
+			    } else if (pch != TO_LOWER (ch))
+		                    break
+	                } else if (IS_LOWER (ch)) {
+			    if (IS_LOWER (pch)) {
+		                if (pch != ch)
+		                    break
+			    } else if (pch != TO_UPPER (ch))
+				    break
+	                } else {
+			    if (pch != ch)
+				break
+			}
+		    } else {
+			if (pch != ch)
+			    break
+		    }
+	        }
+	    }
+
+	    # If the above loop was exited before the end of the pattern
+	    # was reached, the pattern did not match.
+
+	    if (pat[pp] == EOS) {
+		first_char = ip
+		last_char = i-1
+		return (i)
+
+	    } else if (bolflag || str[i] == EOS)
+		break
+	}
+
+	return (0)				# no match
+end