Skip to main content

optionally run several commands when starting tmux


I have a ~/.tmux/dev file which looks like this:


selectp -t 0    # select the first pane
splitw -h -p 50 # split it into two halves

selectp -t 1    # select the new, second (1) pane
splitw -v -p 50 # split it into two halves

selectp -t 0    # go back to the first pane
send-keys 'vim .' Enter

If I run tmux source-file ~/.tmux/dev from inside a tmux session, it works fine.


I want to create a bash script that opens tmux and automatically runs those commands.


I tried running


tmux new 'tmux source-file ~/.tmux/dev'

but I only see two panes; the pane with vim is missing.


I have read How do I get tmux to open up a set of panes without manually entering them?, but before installing a tool for managing tmux configs, I would like to grok what's happening here.


Thanks in advance for any light you can shed on the subject.



Answer



This is what is happening:




  1. tmux new 'tmux source-file ~/.tmux/dev'


    The new commands creates a new session with a single window that has a single pane. The command tmux source-file ~/.tmux/dev runs in this new pane.



    • So, you have a new session N (where N is some number), with

    • a single window N:0 (or whatever you have base-index set to), with

    • a single pane N:0.0 (or whatever you have base-pane-index set to),

    • running the command tmux source-file ~/.tmux/dev.




  2. The source-file command is processed.



    1. The extra panes are added.

    2. Pane 0 is (re)selected.

    3. The send-keys command then “types” vim . + Enter at pane 0.
      This input is ignored because this pane is just running the tmux client that sent the source-file command.



  3. The tmux client exits, thus closing pane 0.


So the unexpected bit is that pane 0 (i.e. N:0.0) is running (only) the source-file command which ignores your “typed” command. This pane never runs an interactive shell that could interpret the “typed” command.


There are at least a couple of ways you can fix this:




  • Start ~/.tmux/dev with new-window so that pane 0 is running your “default command” (i.e. probably an interactive shell).


    This method has the benefit of not assuming that your current pane is running an interactive shell, and also not assuming that the current pane is 0 (i.e. what happens if you run your original series of commands against a pane that is part of an already split window?). It means you can safely bind source-file ~/.tmux/dev to a key that you can run in any context (since it creates a new window for all of its panes). From the shell you can run either tmux source-file ~/.tmux/dev (to create a new window in the current session), or your original tmux new 'tmux source-file ~/.tmux/dev' to create a new session.


    A minor drawback to this method is that when you run tmux new 'tmux source-file ~/.tmux/dev', the initial window will still run the client that sends source-file and exit fairly quickly. This means that your “main window” (the one with the splits) will be one higher than your base-index and a future new window will be placed before the “main window”. You could fix this by using something like this:


    tmux new 'tmux move-window -t 99 \; source-file ~/.tmux/dev'

    It moves the (ephemeral) initial window to a high index so that the new-window in ~/.tmux/dev will end up at base-index.




  • Use (e.g.) tmux new 'tmux source-file ~/.tmux/dev ; zsh -l' so that the pane ends up running an interactive shell after the source-file command finishes.


    The ugly bit about this is that you end up “hard coding” your preferred shell into this command. Also, the send-keys input (vim . + Enter) is technically sent before the shell starts; this is probably okay, but may not always be completely reliable.


    You could avoid “hard coding” your shell by querying tmux for the default-command (or if that is not set, default-shell (or if that is not set, using SHELL)), but that may be more work than you really want to do.




Comments

Post a Comment

Popular Posts

Use Google instead of Bing with Windows 10 search

I want to use Google Chrome and Google search instead of Bing when I search in Windows 10. Google Chrome is launched when I click on web, but it's Bing search. (My default search engine on Google and Edge is http://www.google.com ) I haven't found how to configure that. Someone can help me ? Answer There is no way to change the default in Cortana itself but you can redirect it in Chrome. You said that it opens the results in the Chrome browser but it used Bing search right? There's a Chrome extension now that will redirect Bing to Google, DuckDuckGo, or Yahoo , whichever you prefer. More information on that in the second link.
Post a Comment
Read more

linux - Using an index to make grep faster?

I find myself grepping the same codebase over and over. While it works great, each command takes about 10 seconds, so I am thinking about ways to make it faster. So can grep use some sort of index? I understand an index probably won't help for complicated regexps, but I use mostly very simple patters. Does an indexer exist for this case? EDIT: I know about ctags and the like, but I would like to do full-text search. Answer what about cscope , does this match your shoes? Allows searching code for: all references to a symbol global definitions functions called by a function functions calling a function text string regular expression pattern a file files including a file
Post a Comment
Read more

How do I transmit a single hexadecimal value serial data in PuTTY using an Alt code?

I am trying to sent a specific hexadecimal value across a serial COM port using PuTTY. Specifically, I want to send the hex codes 9C, B6, FC, and 8B. I have looked up the Alt codes for these and they are 156, 182, 252, and 139 respectively. However, whenever I input the Alt codes, a preceding hex value of C2 is sent before 9C, B6, and 8B so the values that are sent are C2 9C, C2 B6, and C2 8B. The value for FC is changed to C3 FC. Why are these values being placed before the hex value and why is FC being changed altogether? To me, it seems like there is a problem internally converting the Alt code to hex. Is there a way to directly input hex values without using Alt codes in PuTTY? Answer What you're seeing is just ordinary text character set conversion. As far as PuTTY is concerned, you are typing (and reading) text , not raw binary data, therefore it has to convert the text to bytes in whatever configured character set before sending it over the wire. In other words, when y
Post a Comment
Read more

networking - Windows 10, can ping other PC but cannot access shared folders! What gives?

I have a computer running Windows 7 that shares a Git repo on drive D. Let's call this PC " win7 ". This repo is the origin of a project that we push to and pull from. The network is a wireless network. One PC on this network is running on Windows 10. Let's call this PC " win10 ". Win10 can ping every other PC on the network including win7 . Win7 can ping win10 . Win7 can access all shared files on win10 . Neither of the PCs have passwords. Problem : Win10 cannot access any shared files on win7 , not from Explorer, nor from Git Bash or any other Git management system (E-Git on Eclipse or Visual Studio). So, win10 cannot pull/push. Every other PC on the network can access win7 shared files and push/pull to/from the shared Git origin. What's wrong with Windows 10? I have tried these: Control Panel\All Control Panel Items\Network and Sharing Center\Advanced sharing settings\ File sharing is on, Discovery is on, Password protected sharing is off Adapte
Post a Comment
Read more