SSH inside SSH fails with “stdin: is not a tty”
I’m trying to connect to machine one with ssh and then connect to another machine two with ssh, but I get this error.
command-line
sponge from moreutils – what’s the difference to shell redirect? useful examples?
sponge reads standard input and writes it out to the specified file.
Unlike a shell redirect, sponge soaks up all its input before writing
the output file. This allows constructing pipelines that read from
and write to the same file.
What are the standard error codes in Linux?
When I write Bash code, for example to copy files, if a file doesn’t exist, in the terminal I see an error similar to file not found. If the user running the script doesn’t have the necessary permissions, the error is similar to permission denied.
What is the email matching regex in basic regex for grep?
I created a text file and put some email addresses in it. Then I used grep to find them. Indeed it worked:
How to signal the end of stdin input
In Bash, I learned that the ending signal can be changed by here document. But by default how can I signal the end of stdin input? I happened to find that with cat and chardet, their stdin inputs can be signaled as finished by Ctrl+D. But I seems to remember that Ctrl+D and Ctrl+C are … Read more
How to find list of available shells by command-line?
How to list available shells for use by command-line?
command to layout tab separated list nicely
Sometimes, I’m getting as an input tab separated list, which is not quite aligned, for instance
How can I edit multiple files in Vim?
I know I can open multiple files with vim by doing something like vim 2011-12*.log, but how can I switch between files and close the files one at a time?
Find only destination of symlink
For use in a shell-script, I’m looking for a commandline-way to get the destination of a symbolic link. The closest I’ve come so far is stat -N src, which outputs src -> dst. Of course I could parse the output and get dst, but I wonder if there is some direct way of getting the destination.
How to use ifconfig to show active interface only
By default ifconfig will show me all available interfaces , but what if I just want to display active ones? Like, en0 only in below.