Thread: redirecting - 'permission denied'

Hi, I want to redirect the output of the 'ls' command into a file. For example "ls -Fa | ./newfile.text"
However I am getting the 'permission denied' error. Am I going about this the correct way?

Thanks for the reply. I just realized that 'redirecting' is possibly the wrong word to use for the | symbol. Anyway I 'd like to stick to using '|' . Any advice would be helpful, thanks

Originally Posted by MK27

You can't do that because:

1) You are trying to stream the output through a pipe, which is not quite the same as simple redirection.
2) There is no process on the other end of the pipe -- there is a non-executable file, hence "permission is denied".

Hopefully you understand *nix file modes. These are set/read as a mask. The first part of the mask refers to the owner, the 2nd to the owner's group, the third to everyone else. The mask is:

1: executable
2: writable
4: readable

So 6 means read/write permission (4+2). 640 would mean the owner can read/write the file, the owner's group can read the file, and everyone else has no access to the file.

Text files are usually set some combination of 6 4 and 0 because you do not execute a text file (executable scripts excepted). So if you try and execute a text file set 666 -- which means anyone can read or write it -- you will get permission denied, because the executable "bit" (1) is not set.
Executables are usually set 7 or 5 (read + write + execute, or read + execute). 1 (execute only) is oxymoronic because a file must be read to be executed.

But you do not want to execute newfile.text anyway, you want to write the output of ls into it. For that use:

ls > newfile.text

Notice, redirection uses >, not |. | is a pipe.

Thanks for that information.

If I wanted to use the following command....

ls -Fa | file1 (where file1 is an exe)

what should happen? This is off topic, sorry about that

Originally Posted by jeffcobb

Perhaps if you:
1. Moved this to the Linux subforum here and...
2. Explained what you are *really* trying to do...

You might get some help...

Yep will do, thanks

Originally Posted by jeffcobb

file1 would get the output of ls -Fa as an input stream and if the program "file1" was set up to do so, it would process it....for example:

ls -Fa | grep foo

would effectively be a filter, only emitting lines that contained the string "foo"...

Final question on this........


So file1 needs to be set up (ie coded with input parameters or whatever) to take in the output?

Originally Posted by MK27

It needs to be a functioning program that process stdin, yes.

If anyone could point me in the direction of simple examples of how to accept input from either the command line or other files I'd appreciate it, thanks.

As jeffcobb stated previously, please ask these questions on a Linux/Shell forum.

This is an excellent one: Shell Programming and Scripting - The UNIX and Linux Forums