Skip to main content

How to unfreeze after accidentally pressing Ctrl-S in a terminal?

By
This feature is called Software Flow Control (XON/XOFF flow control)

When one end of the data link (in this case the terminal emulator) can't receive any more data (because the buffer is full or nearing full or the user sends C-s) it will send an "XOFF" to tell the sending end of the data link to pause until the "XON" signal is received.

What is happening under the hood is the "XOFF" is telling the TTY driver in the kernel to put the process that is sending data into a sleep state (like pausing a movie) until the TTY driver is sent an "XON" to tell the kernel to resume the process as if it were never stopped in the first place.

C-s enables terminal scroll lock. Which prevents your terminal from scrolling (By sending an "XOFF" signal to pause the output of the software).

C-q disables the scroll lock. Resuming terminal scrolling (By sending an "XON" signal to resume the output of the software).

This feature is legacy (back from the 80's when terminals were very slow and did not allow scrolling) and is enabled by default.

To disable this feature you need the following in either ~/.bash_profile or ~/.bashrc:
stty -ixon
Labels:

Comments

Post a Comment

Popular posts from this blog

How to grep the output of cURL?

By
curl writes the output to stderr, so redirect that and also suppress the progress: curl - v -- silent https :// google . com / 2 >& 1 | grep expire The reason why  curl  writes the information to stderr is so you can do: curl <url> | someprgram  without that information clobbering the input of  someprogram It is possible to use  --stderr -  as parameter, to redirect the output from stderr (default) to stdout. With this option you also should use  --silent  to suppress the progress bar. $ curl - v -- silent https :// google . com / -- stderr - | grep expire * expire date : 2015 - 09 - 01 00 : 00 : 00 GMT  
Post a Comment
Read more

Salt stack issues

By
The function “state.apply” is running as PID Restart salt-minion with command:  service salt-minion restart No matching sls found for ‘init’ in env ‘base’ Add top.sls file in the directory where your main sls file is present. Create the file as follows: 1 2 3 base: 'web*' : - apache If the sls is present in a subdirectory elasticsearch/init.sls then write the top.sls as: 1 2 3 base: '*' : - elasticsearch.init How to execute saltstack-formulas create file  /srv/pillar/top.sls  with content: base : ' * ' : - salt create file  /srv/pillar/salt.sls  with content: salt : master : worker_threads : 2 fileserver_backend : - roots - git gitfs_remotes : - git://github.com/saltstack-formulas/epel-formula.git - git://github.com/saltstack-formulas/git-formula.git - git://github.com/saltstack-formulas/nano-formula.git - git://github.com/saltstack-f...
12 comments
Read more

Terraform

By
Terraform is a tool for building, changing, and versioning infrastructure safely and efficiently. Terraform can manage existing and popular service providers as well as custom in-house solutions. Configuration files describe to Terraform the components needed to run a single application or your entire datacenter. Terraform generates an execution plan describing what it will do to reach the desired state, and then executes it to build the described infrastructure. As the configuration changes, Terraform is able to determine what changed and create incremental execution plans which can be applied. The infrastructure Terraform can manage includes low-level components such as compute instances, storage, and networking, as well as high-level components such as DNS entries, SaaS features, etc. The key features of Terraform are: Infrastructure as Code : Infrastructure is described using a high-level configuration syntax. This allows a blueprint of your datacenter to be versioned and...
16 comments
Read more