Oct 28, 2013 How to Show the User Library Folder in OS X Mavericks. All of the latest versions of OS X have opted for a conservative approach to showing the users /Library/ directory, a folder which contains a variety of important files, settings, preferences, caches, and many specific files that are required for apps to run as intended. Jul 27, 2014 In OS X, Spotlight is an effective way to search your entire hard drive for a file or folder, email, or any other file. There are many other things Spotlight can do, and searching for files is. Aug 04, 2017 How to search into a specific folder and its subfolders on macOS Mac OS X Sierra,Mojave Search in a particular folder and subfolder through Spotlight Change Finder Search to Look In Current Folder.
program'. If that doesn't help, it's probably because you're wondering what a Mac Os X Search For Folder Name In Specific Windows 10regular expression ('re' or 'regex') is. Basically, it's a pattern used to describe a string of characters, and if you want to know aaaaaaall about them, I highly recommend reading Mastering Regular Expressions by Jeffrey Friedl and published by Unix 端ber-publisher O'Reilly & Associates.
Regexes (regices, regexen, ...the pluralization is a matter of debate) are an extremely
useful tool for any kind of text processing. Searching for patterns with grep is most people's first exposure to them, as like the article says, you can use them to search for a literal pattern within any number of text files on your computer. The cool thing is that it doesn't have to be a literal pattern, but can be as complex as you'd like.
The key to this is understanding that certain characters are 'metacharacters', which have
special meaning for the regex-using program. For example, a plus character (+) tells the program to match one or more instances of whatever immediately precedes it, while parentheses serve to treat whatever is contained as a unit. Thus, 'ha+' matches 'ha', but it also matches 'haa' and 'haaaaaaaaaaa', but not 'hahaha'. If you want to match the word 'ha', you can use '(ha)+' to match one or more instances of it, such as 'hahaha' and 'hahahahahahahahaha'. Using a vertical bar allows alternate matching, so '(ha|ho)+' matches 'hohoho', 'hahaha', and 'hahohahohohohaha'. Etc.
There are many of these metacharacters to keep in mind. Inside brackets ([]), a carat (^)
means that you don't want to match whatever follows inside the brackets. For Magritte fans, '[^(a cigar)]' matches any text that is not 'a cigar'. The rest of the time, the carat tells the program to match only at the beginning of a line, while a dollar sign ($) matches only at the end. Therefore, '^everything$' matches the word 'everything' only when it is on a line all by itself and '^[^(anything else)]' matches all lines that do not begin with 'anything else'.
The period (.) matches any character at all, and the asterisk (*) matches zero or more times.
Compare this to the plus, which matches one or more times -- a subtle but important difference. A lot of regular expressions look for '.*', which is zero or more of anything (that is, anything at all). This is useful when searching for two things that might or might not have anything else (that you probably don't care about) between them: 'foo.*bar' will match on 'foobar', 'foo bar' & 'foo boo a wop bop a lop bam boo bar'. Changing the previous example to a plus, 'foo.+bar', requires that anything -- come between foo and bar, but it doesn't matter what, so 'foobar' doesn't match but the other two examples given do match.
For details, try the man pages -- 'man grep'. There are a lot of different versions of the
program, so details may vary. All of this should be valid for OSX though.
Confusing? Maybe, but regular expressions aren't that bad when you get used to them, and
they can be a very useful tool to take advantage of it you know what you're doing. An example.
Let's say you have an website stored on your computer as a series of html documents.
As a cutting edge developer, you've seen the CSS light and want to delete all the tags wherever they're just saying e.g. face='sans-serif' &/or size='12', because the stylesheet can now do that for you. On the other hand, it's possible that the patterns 'face='sans-serif' or 'size='12' could show up in normal text (though admittedly that's unlikely). In fact, what you really want to know is wherever those patterns show up in a font tag, but you don't care about anywhere else that they might appear. Here's one way to find that pattern:
This does a number of things. The -i tells grep to ignore case (otherwise it's case sensitive,
and won't match 'FONT' if you're looking for 'font' or 'Font'). The -r tells it to recursively descend through the directories from wherever the command starts -- in this case, all htm and html files in the current directory. Everything in single quotes is the pattern we're matching. We tell grep to match on any text that starts with ' (thus staying within the font tag), and then either the face or size definition that we're interested in. The one glitch here is that line breaks can break things, though there are various ways around that. Finding them is left as the proverbial exercise for the reader. :)
The next question is, what do you want to do with this information you've come up with?
Presumably you want to edit those files in order to fix them, right? With that in mind, maybe it would be useful to just make a list of matches. Grep normally outputs all the lines that match the pattern, but if you just want the filenames, use the -l switch. If you want to save the results into a file, redirect the output of the command accordingly. With those changes, we now have:
Great. But we can do better still. If you are comforable with the vi editor, you can call vi
with that command directly. The trick is to wrap the command in backticks (`). This is a cool little Unix trick that runs the contained command & returns the result for whatever you want to do with it. Thus you can simply put this command:
The result of this command, as far as your tcsh shell is concerned, is something along the lines
of
etc. The beautiful thing here is that if you quit vi & re-run the command later, it will be
able to effectively 'pick up where you left off', since files you've already edited will presumably no longer match the grep command. Mac Os X Search For Folder Name In Specific Meaning
And if you want to get really ambitious, you can use these techniques in ways that
allow you to do all your editing directly from the command line, without having to go into an interactive editor such as vi or emacs or whatever. If you make it this far in your experiments, then the next step is to learn to filter the results of a match and process the filtered data in some way, using tools such as sed, awk, and perl. Using these tools, you can find all instances of the pattern in question, break it down however you like, substitute or shuffle the parts around however you like, and then build it all back up again. This is fun stuff! By this point, you're getting pretty heavily into Unix arcana, and the best book that I've seen about these tricks is O'Reilly's Unix Power Tools, by various authors. If you really want to leverage the power of the tools that all Unixes come with, including OSX, then this is a great place to both start & end up. There's plenty of material in there to keep you busy for months & years... Comments are closed.
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