How to use grep on all files non-recursively in a directory?

Question

I want to search for a string of text in all files in a directory (and not its subdirectories; I know the -r option does that, but that is not what I want).

Running
```
grep "string" /path/to/dir
```
is supposed to be able to do this, I've read, but it gives me the error:

grep: dir: Is a directory
Next, I tried running grep on multiple files.

grep "string" .bashrc .bash_aliases works perfectly.

grep "string" .bash* works as intended too.

grep "string" * gives me the errors:
```
grep: data: Is a directory
grep: Desktop: Is a directory
grep: Documents: Is a directory
grep: Downloads: Is a directory
...
```

Only the errors are printed, I don't get the matching lines. I tried using the -s option, but to no avail.

So, my questions:

Why am I not being able to use grep on a directory, as in (1), when I should be able to? I've seen that done in plenty examples on the Internet.
Edit: When I say "using grep on a directory", I mean "search in all the files in that directory excluding its subdirectories". I believe that this is what grep does when you pass a directory to it in place of a file. Am I incorrect?
Please give me an explanation on the workings of grep that would explain the behavior of commands in (2).
Edit: Let me be more specific. Why does using wildcards to specify multiple files to search in for work with .bash* and not with * or even ./*?
How can I search all the files in a directory (and not its subdirectories) using grep?

Also you're relying on the shell expanding wildcards such as `*`, known as globbing. Globbing does not include filenames starting with a dot such as `.bashrc` as standard. You can set shell options so that it will include these files, but you can get yourself in a bit of a mess if you don't know what you're doing. A good guide to understanding globing can be found here http://mywiki.wooledge.org/glob — Arronical, May 25 '16 at 16:23
I dunno why, but I've always done globbing on hidden files, and it has always worked. I haven't change any setting or something. As I pointed out in (2), it works with `grep "string" .bash*` too. — John Red, May 25 '16 at 16:32
Sorry, my last example was incorrect. You can search in hidden files as well, and suppressing the "is a directory" because Linux technically sees directories as a different type of file. The command would be then: `grep "string" * .* 2>/dev/null` or `grep -s "string" * .*` — Terrance, May 25 '16 at 16:55

wjandrea · Accepted Answer · 2019-03-05T22:13:25.783

57

In Bash, a glob will not expand into hidden files, so if you want to search all the files in a directory, you need to specify hidden files .* and non-hidden *.

To avoid the "Is a directory" errors, you could use -d skip, but on my system I also get an error grep: .gvfs: Permission denied^†, so I suggest using -s, which hides all error messages.

So the command you are looking for is:

grep -s "string" * .*

If you are searching files in another dir:

grep -s "string" /path/to/dir/{*,.*}

Another option is to use the dotglob shell option, which will make a glob include hidden files.

shopt -s dotglob
grep -s "string" *

For files in another dir:

grep -s "string" /path/to/dir/*

† Someone mentioned that I shouldn't get this error. They may be right - I did some reading but couldn't make heads or tails of it myself.

edited Mar 05 '19 at 22:13

answered May 25 '16 at 18:53

wjandrea

14,109
4
48
98

1

Is there any reason for the space between `*` and `.*`? – Hashim Aziz Sep 23 '18 at 00:35
2

@Hashim Compare the output of `echo * .*` and `echo *.*` run in your home directory, and the difference should be obvious. Otherwise LMK and I'll explain it. – wjandrea Sep 23 '18 at 01:03
Interesting, so `echo *` shows non-hidden files and folders, `echo *.*` shows non-hidden files, `echo .*` shows all files, and `echo * .*` shows all files and directories. But why the reason for the space between the two in the latter case? It feels messy to me. Is there not a way to combine the two to get the same results? Or otherwise is there a syntax explanation of why the two need to be separated here, or is `* .*` an exceptional case? – Hashim Aziz Sep 23 '18 at 02:00
1

@Hashim I'm not sure how you came to those conclusions, so let me explain. First, directories are files in this context. In globs, `*` represents all non-hidden files (i.e. filenames which **don't** start with a dot); `.*` represents all hidden files (i.e. filenames that **do** start with a dot); and `*.*` represents all non-hidden files which **contain** a dot. In `echo * .*`, the two globs must be separate because they are different globs: one for non-hidden, one for hidden. Though as I wrote in my answer, you can make `*` include hidden files by turning on the `dotglob` shell option. – wjandrea Sep 23 '18 at 02:23
1

Using `*.*` is common on Windows (DOS) as a way to list all files but on *nix will only include files with a dot in them, so it doesn't make sense on *nix. Instead you use `*` to list all files except hidden files, and `.*` to list hidden files. – thomasrutter Mar 06 '19 at 01:05

anonymous2 · Answer 2 · 2019-12-04T12:31:06.390

12

You need the -d skip option added on.

Grep is searching inside of files. You can search recursively, as you said, if you want to search files inside of a directory.
By default, grep will read all files, and it detects the directories. Because by default you have not defined what to do with the directories with the -d option, it give error output.
Searching just within the parent directory would be grep -d skip "string" ./*

edited Dec 04 '19 at 12:31

answered May 25 '16 at 16:13

anonymous2

4,268
7
33
61

For more information on grep, see `man grep`. – anonymous2 May 25 '16 at 16:14
(a) Please see the edit. (b) Using `-d skip` does not work; it's basically the same as `-s`; also, see the edit. (c) Nope, `grep -d skip "string" ./*` does not work either. – John Red May 25 '16 at 16:40

score 8 · Answer 3 · edited May 26 '16 at 01:22

8

Old timers would probably do this:

find . -type f -print0 | xargs -0 grep "string"

edited May 26 '16 at 01:22

Digital Trauma

2,415
15
24

answered May 26 '16 at 00:25

dathompson

81
1

3

Why not `find . -type f -exec grep string {} +`? – wchargin May 26 '16 at 01:07
6

You also want `-maxdepth 1`. – wchargin May 26 '16 at 05:48
@wchargin: if you want the file name in the output when there's only one file I think you want `find . -type f -maxdepth 1 -exec grep string /dev/null {} +` – Greg Nisbet Mar 14 '19 at 06:27
1

@GregoryNisbet: Just pass `-H` to grep. – wchargin Mar 14 '19 at 17:23

score 2 · Answer 4 · answered Feb 23 '20 at 21:20

You can think like this, for example using grep.

grep -l PATH ~/.[^.]*

So this search for string "PATH" listing name of the files below the user's home directory, only for files that start with a dot .

/root/.bash_history
/root/.bash_profile
grep: /root/.cache: Is a directory
grep: /root/.config: Is a directory
grep: /root/.dbus: Is a directory

Using grep PATH ~/.[^.]* you'll see all occurrence, including line with searching keyword.

/root/.bash_history:echo $PATH
/root/.bash_history:echo $PATH
/root/.bash_history:PATH=$PATH:~/bin
/root/.bash_history:echo $PATH
/root/.bash_profile:PATH=$PATH:$HOME/bin
/root/.bash_profile:export PATH
grep: /root/.cache: Is a directory
grep: /root/.config: Is a directory
grep: /root/.dbus: Is a directory

To get rid of error redirect to /dev/null for example

grep PATH ~/.[^.]* 2>/dev/null

/root/.bash_history:echo $PATH
/root/.bash_history:echo $PATH
/root/.bash_history:PATH=$PATH:~/bin
/root/.bash_history:echo $PATH
/root/.bash_profile:PATH=$PATH:$HOME/bin
/root/.bash_profile:export PATH

So you can apply this pattern for searching "Apache" string in files from /etc directory-looking only in files below this main directory. You see that this don't return from /etc/httpd/conf/httpd.conf

grep Apache /etc/[^.]* 2>/dev/null
/etc/passwd:apache:x:48:48:Apache:/usr/share/httpd:/sbin/nologin
/etc/services:derby-repli     4851/tcp                # Apache Derby Replication
/etc/services:derby-repli     4851/udp                # Apache Derby Replication

score 2 · Answer 5 · edited May 26 '16 at 01:46

2

Rephrasing - you want to grep the files in one level of subdirectory, but not recurse though all sub-sub directories?

grep forthis  *  */*

Or if you don't want the files in the current directory

grep forthis  */*

Note this won't find directories starting with a dot.

grep forthis  .*/*    */*

should do that job.

There's also -maxdepth and -mindepth restriction parameters available to the find command too.

edited May 26 '16 at 01:46

muru

193,181
53
473
722

answered May 26 '16 at 01:42

Criggie

671
5
12

Wouldn't `grep forthis */*` search files both in the current directory and one directory down? – Hashim Aziz Sep 23 '18 at 00:37
@Hashim nope mostly - cos `*/*` only matches things with one slash. If you had a file named `a/b` in the current directory then `*/* would match that. – Criggie Sep 23 '18 at 04:07

Mojtaba Rezaeian · Answer 6 · 2020-01-29T13:58:25.300

1

Here is an example to properly skip directories without hiding all errors (without -s param on chosen answer):

grep --directories='skip' 'searchString' *

edited Jan 29 '20 at 13:58

answered Oct 03 '19 at 08:56

Mojtaba Rezaeian

111
6

How to use grep on all files non-recursively in a directory?

6 Answers6

Linked