You can use regular expressions for text search in the [Find] dialog box, [Option] dialog box, and Decode Result Filter.

ASTEC Eyes supports following regular expressions:

Patterns	Explanations
Character	One character is the most fundamental pattern in a regular expression. An ordinary character except for metacharacters matches the character itself. For example, the pattern "A" matches the character "A". The metacharacter (having special meaning in a regular expression) preceded by (backslash) is treated as an ordinary character. For example, if you want to search for a character * (asterisk), you must specify * as a pattern since * is a metacharacter. metacharacters for ASTEC Eyes regular expression There are 16 metacharacters for ASTEC Eyes regular expression. (backslash) ^ $ ( ) | . [ - ] * + ? { , } You can also use a Japanese character (Shift JIS encoding, 2 byte character) as ordinary character with Japanese Windows.
Text (concatenation)	You can specify the concatenation of characters as a pattern. For example, the pattern flags matches the character sequence of 'f', 'l', 'a', 'g', 's'. Not only a character but a pattern can be concatenated similarly. The pattern RS concatenating pattern R and S matches R followed by S.
| (alternative)	Pattern R|S matches either pattern R or S. foo|bar matches the text foo or bar.
* (closure)	A pattern followed by * matches 0 or more occurrences of the pattern. For example, ab* matches a, ab, abb, abbb, abbb ... b, and so on.
'(' and ')' (grouping)	Parentheses mean the grouping of patterns. For example, a(bc)* matches a, abc, abcbc, abcbcbc, abcbcbc--bc, and so on. foo(bar|baz) matches both foobar and foobaz.

You can use the following metacharacters with ASTEC Eyes.

Metacharacters	Functions
.	. (period) matches any one character. It is equivalent to the pattern that all the characters are concatenated and enclosed in the parentheses: (a|b|c||0|1|2|||||)
[ and ]	A non-empty string of characters enclosed in square brackets matches any one character in that string. The pattern [abc] matches a, b, or c. It is equivalent to the pattern (a|b|c). The - (minus) is used to indicate a range of consecutive characters. [A-Za-z] matches one of the alphabets in capital or small letter. The order of characters is based on the ASCII code. [ followed by ^ (circumflex) matches one character except the characters after circumflex. [^0-9] matches any characters other than a number. [ and ] make a group of 1 byte ASCII characters. You can not make a group of Japanese characters (Shift JIS encoding, 2 byte character). Metacharacters other than , ^, - and ] are treated as an ordinary character. In addition, ^ has the special meaning only if it occurs immediately after [. It is not necessary to escape the metacharacters except the above four with .
{m ,n }	This pattern matches any number of occurrences between m and n inclusive of the preceding pattern. Where m ≥ 0, n ≥ 1, and m ≤ n. {m,} matches at least m occurrences. {,n} is equivalent to {0, n}. {n} is equivalent to {n, n}, and matches exactly n occurrences.
?	? matches zero or one occurrence of the preceding pattern. R? is equivalent to R{0,1}.
+	+ matches one or more occurrences of the previous pattern. R+ is equivalent to RR* and R{1,}.
^	A ^ (circumflex) at the beginning of an entire pattern matches the beginning of the target text. ^foo matches foobar, but does not match barfoo.
$	A $ (dollar) at the end of an entire pattern matches the end of the target text. foo$ matches barfoo, but does not match foobar.

Following four characters (in the table below) are treated as metacharacters only in specific patterns.

Characters	Patterns treated as metacharacters
^	It is at the beginning of an entire pattern, or immediately after [.
$	It is at the end of an entire pattern.
-	It is enclosed by [ and ].
,	It is enclosed by { and }.

These metacharacters are treated as ordinary characters in the pattern other than above table. It is not necessary to escape by (backslash).

(backslash) followed by a specific character may have special meanings. The sequence of (backslash) and the character is called an escape sequence.
ASTEC Eyes supports the following escape sequences.

Escape sequences	Meanings
a	0x07 (BEL,Alert)
b	0x08 (BS, Back Space)
d	number (equivalent to [0-9])
D	other than number (equivalent to [^0-9])
f	0x0c (FF, Form Feed)
n	0x0a (NL, New Line)
r	0x0d (CR, Carriage Return)
s	white space character (equivalent to [ trnf])
S	other than white space character (equivalent to [^ trnf])
t	0x09 (HT, Horizontal Tab)
w	alphabet and number (equivalent to [0-9 a-zA-Z])
W	other than alphabet and number (equivalent to [^0-9 a-zA-Z])
xhh, Xhh	hh is hexadecimal of single or double digits (0-9, a-f, A-F)