Search a file in Unix - linux

I need to search a file in unix which starts with "catalina"
find ... what to be used effectively -name, -exec ? Whats the expression
Also I need to show few files at a time, then show some more. There are huge set of log files in there. I know there is some expression, but forgot...

find /path/to/search/in -name 'catalina*'
Use iname to match case-insensitively.
To not be overwhelmed with a long list of files, filter through less (append |less). You can also use more instead of less.

If catalina is the file name, then use
find -name 'catalina*'
If catalina is the first word contained in the file, then use
find -type f | xargs head -v -n 1 | grep -B 1 -A 1 -e '^catalina'

Related

"find" specific contents [linux]

I would like to go through all the files in the current directory (or sub-directories) and echoes me back the name of files only if they contain certain words.
More detail:
find -type f -name "*hello *" will give me all file names that have "hello" in their names. But instead of that, I want to search through the files and if that file's content contains "hello" then prints out the name of the file.
Is there a way to approach this?
You can use GNU find and GNU grep as
find /path -type f -exec grep -Hi 'hello' {} +
This is efficient in a way that it doesn't invoke as many grep instances to as many files returned from find. This works in an underlying assumption that find returns a set of files for grep to search on. If you are unsure if the files may not be available, as a fool-proof way, you can use xargs with -r flag, in which case the commands following xargs are executed only if the piped commands return any results
find /path -type f | xargs -r0 grep -Hi 'hello'

Find and sort files by date modified

I know that there are many answers to this question online. However, I would like to know if this alternate solution would work:
ls -lt `find . -name "*.jpg" -print | head -10`
I'm aware of course that this will only give me the first 10 results. The reason I'm asking is because I'm not sure whether the ls is executing separately for each result of find or not. Thanks
In your solution:
the ls will be executed after the find is evaluated
it is likely that find will yield too many results for ls to process, in which case you might want to look at the xargs command
This should work better:
find . -type f -print0 | xargs -0 stat -f"%m %Sm %N" | sort -rn
The three parts of the command to this:
find all files and print their path
use xargs to process the (long) list of files and print out the modification unixtime, human readable time, and filename for each file
sort the resulting list in reverse numerical order
The main trick is to add the numerical unixtime when the files were last modified to the beginning of the lines, and then sort them.

find -exec doesn't recognize argument

I'm trying to count the total lines in the files within a directory. To do this I am trying to use a combination of find and wc. However, when I run find . -exec wc -l {}\;, I recieve the error find: missing argument to -exec. I can't see any apparent issues, any ideas?
You simply need a space between {} and \;
find . -exec wc -l {} \;
Note that if there are any sub-directories from the current location, wc will generate an error message for each of them that looks something like that:
wc: ./subdir: Is a directory
To avoid that problem, you may want to tell find to restrict the search to files :
find . -type f -exec wc -l {} \;
Another note: good idea using the -exec option . Too many times people pipe commands together thinking to get the same result, for instance here it would be :
find . -type f | xargs wc -l
The problem with piping commands in such a manner is that it breaks if any files has spaces in it. For instance here if a file name was "a b" , wc would receive "a" and then "b" separately and you would obviously get 2 error messages: a: no such file and b: no such file.
Unless you know for a fact that your file names never have any spaces in them (or non-printable characters), if you do need to pipe commands together, you need to tell all the tools you are piping together to use the NULL character (\0) as a separator instead of a space. So the previous command would become:
find . -type f -print0 | xargs -0 wc -l
With version 4.0 or later of bash, you don't need your find command at all:
shopt -s globstar
wc -l **/*
There's no simple way to skip directories, which as pointed out by Gui Rava you might want to do, unless you can differentiate files and directories by name alone. For example, maybe directories never have . in their name, while all the files have at least one extension:
wc -l **/*.*

Linux - Find files that do not contain certain characters

I understand that using something like [^a]* will output all the files that do not start with "a".
If I want to echo files that contain at least 5 characters that do not start with "abc" (but can contain "abc" in the middle of the filename), how should I go about doing so?
I have
echo [^abc]?????*
but the output also removes files like "123abc", which I don't quite understand.
You don't indicate which OS your question applies to, but one way to determine the set of matching files on Mac OS X or Linux would be:
find . -maxdepth 1 -type f -name "?????*" | egrep -v "./abc"
Note that this will list only files in the current directory. If you want to include files in subdirectories, you'll need to remove the maxdepth argument.
Also note that these commands are case-sensitive. You'll need to use -iname and -i to make them case-insensitive.
EDIT:
If you really need to use the echo command, the following will work:
echo `find . -maxdepth 1 -type f -name "?????*" | egrep -v "./abc"`

What's the best way to find a string/regex match in files recursively? (UNIX)

I have had to do this several times, usually when trying to find in what files a variable or a function is used.
I remember using xargs with grep in the past to do this, but I am wondering if there are any easier ways.
grep -r REGEX .
Replace . with whatever directory you want to search from.
The portable method* of doing this is
find . -type f -print0 | xargs -0 grep pattern
-print0 tells find to use ASCII nuls as the separator and -0 tells xargs the same thing. If you don't use them you will get errors on files and directories that contain spaces in their names.
* as opposed to grep -r, grep -R, or grep --recursive which only work on some machines.
This is one of the cases for which I've started using ack (http://petdance.com/ack/) in lieu of grep. From the site, you can get instructions to install it as a Perl CPAN component, or you can get a self-contained version that can be installed without dealing with dependencies.
Besides the fact that it defaults to recursive searching, it allows you to use Perl-strength regular expressions, use regex's to choose files to search, etc. It has an impressive list of options. I recommend visiting the site and checking it out. I've found it extremely easy to use, and there are tips for integrating it with vi(m), emacs, and even TextMate if you use that.
If you're looking for a string match, use
fgrep -r pattern .
which is faster than using grep.
More about the subject here: http://www.mkssoftware.com/docs/man1/grep.1.asp
grep -r if you're using GNU grep, which comes with most Linux distros.
On most UNIXes it's not installed by default so try this instead:
find . -type f | xargs grep regex
If you use the zsh shell you can use
grep REGEX **/*
or
grep REGEX **/*.java
This can run out of steam if there are too many matching files.
The canonical way though is to use find with exec.
find . -name '*.java' -exec grep REGEX {} \;
or
find . -type f -exec grep REGEX {} \;
The 'type f' bit just means type of file and will match all files.
I suggest changing the answer to:
grep REGEX -r .
The -r switch doesn't indicate regular expression. It tells grep to recurse into the directory provided.
This is a great way to find the exact expression recursively with one or more file types:
find . \\( -name '\''*.java'\'' -o -name '\''*.xml'\'' \\) | xargs egrep
(internal single quotes)
Where
-name '\''*.<filetype>'\'' -o
(again single quotes here)
is repeated in the parenthesis ( ) for how many more filetypes you want to add to your recursive search
an alias looks like this in bash
alias fnd='find . \\( -name '\''*.java'\'' -o -name '\''*.xml'\'' \\) | xargs egrep'

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