How to read dash files

How can I read a dash file from the terminal other than delimiting it with ./

For example to read a - file we can read it by

cat ./-file_name

Q: Is there an alternative way to achieve the same thing?

Answers:

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Method 1

Use double -- to mark end of options:

cat -- -<FILENAME>

Other programs such as touch, rm or git checkout also follow this convention:

$ touch -- -file
$ ll
total 0
-rw-r--r-- 1 ja ja 0 Mar 10 13:13 -file
$ echo hi! >> -file
$ cat -- -file
hi!
$ rm -- -file
$ echo $?
0

WARNING: It’s good practice to always use -- after rm in scripts. An attacker could place --rf file in a directory and rm * would take it as run parameters. See this:

$ touch A
$ touch B
$ mkdir dir
$ touch dir/C
$ touch -- -rf
$ rm *
$ ll
total 0
-rw-r--r-- 1 ja ja 0 Mar 10 13:21 -rf

Oops, this is not we meant, we didn’t want to remove directories. We should have used --:

$ touch A
$ touch B
$ mkdir dir
$ touch dir/C
$ touch -- -rf
$ rm -- *
rm: cannot remove `dir': Is a directory
$ ll
total 4.0K
drwxr-xr-x 2 ja ja 4.0K Mar 10 13:22 dir

Method 2

For commands which get input from stdin, you can use redirection:

cat <-file_name

Method 3

Alternatives become weird:

dd if=-x 2>/dev/null

All methods was sourced from stackoverflow.com or stackexchange.com, is licensed under cc by-sa 2.5, cc by-sa 3.0 and cc by-sa 4.0