In order to pass these through correctly, you must escape them in your script. Note: When passing grep patterns to BBEdit via AppleScript, be aware that both the backslash and double-quote characters have special meaning to AppleScript. BBEdit's grep syntax coloring helps make this clear. So, most characters match themselves, and even the special characters will match themselves if they are preceded by a backslash. But what if you only want to match a literal dot? If you escape the dot: "\.", it will only match another literal dot character in your text. In grep, a dot character will match any character except a return. To search for a backslash character itself, double it \\ so that its first appearance will escape the second.įor example, perhaps the most common "special character" in grep is the dot: ".". In this case, you must use the backslash character \ before that special character to have it be treated literally this is known as "escaping" the special character. However, sometimes you will need to include an exact, or literal, instance of these characters in your grep pattern. (The use of these characters is covered in the following sections.) In addition to the simple character matching discussed above, there are various special characters that have different meanings when used in a grep pattern than in a normal search. Very simple patterns, to be sure, but patterns nonetheless. This idea is so obvious that it seems not worth mentioning, but the important thing to remember is that these characters are search patterns. For instance, if you are looking for the letter "t", Grep stops and reports a match when it encounters a "t" in the text. myfiles1, myfiles2 etc) but won't remove a file with the number 9 anywhere within it's name.Most characters that you type into the Find dialog box match themselves. For example, rm myfile will remove all myfiles* (ie. This will match anything that is not listed within those square brackets. This is the equivalent of in standard wildcards. You may need to add a '\' (backslash) before this command to work, because the shell may attempt to interpret this as a pipe. This way you can search for something or something else (possibly using two different regular expressions). This wildcard makes a logical OR relationship between wildcards. This kind of wildcard specifies an “or” relationship (you only need one to match). For example, these would work: mam, mbm, mcm, mdm. If you did mm it can become: mam, mum, mom if you did: mm it can become anything that starts and ends with m and has any character a to d inbetween. So "a$" means find a line ending with an "a".įor example, this command searches the file myfile for lines starting with an "s" and ending with an "n", and prints them to the standard output (screen): cat myfile | grep '^s.*n$' (square brackets) So "^a" means find a line starting with an "a". n* will match n, nn, nnnn, nnnnnnn but not na or any other character. The proceeding item is to be matched zero or more times. Is used to match any string, equivalent to * in standard wildcards. Note you may need to use quotation marks and backslash(es).* (dot and asterisk) to protect a subsequent special character. Thus, "m.a" matches "mpa" and "mea" but not "ma" or "mppa". Will match any single character, equivalent to ? (question mark) in standard wildcard expressions. Note you may need to use quotation marks and backslash(es). myfiles1, myfiles2 etc) but won't remove a file with the number 9 anywhere within it's name. For example rm myfile will remove all myfiles* (ie. This construct is similar to the construct, except rather than matching any characters inside the brackets, it'll match any character, as long as it is not listed between the. Note that spaces are not allowed after the commas (or anywhere else). "m*l" could by mill, mull, ml, and anything that starts with an m and ends with an l. If you specified a "cd*" it would use "cda", "cdrom", "cdrecord" and anything that starts with “cd” also including “cd” itself. This can represent any number of characters (including zero, in other words, zero or more characters). If you specified something at the command line like "hd?" GNU/Linux would look for hda, hdb, hdc and every other letter/number between a-z, 0-9.
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