Linux Most Used Commands 2

Handy Git Commands

https://neelquestforlearning.blogspot.com/2023/07/handy-git-commands-for-hard-core.html

How to view live kernel debug logs from printk

tail -f /var/log/kern.log

GDB Notes

https://neelquestforlearning.blogspot.com/2021/12/my-gdb-notes.html

How to iw commands to Air capture the packet

http://ict.siit.tu.ac.th/help/iw

How to enable monitor mode in ubuntu laptop

sudo iw phy phy0 interface add mon0 type monitor
sudo iw dev wlan0 del       

sudo ifconfig mon0 up

Disable Monitor Mode

You cannot use your WiFi device for both transmitting and monitoring at the same time. If you want to return to normal (managed) mode after performing monitoring then delete the monitoring interface down and add the normal interface
sudo iw dev mon0 del
sudo iw phy phy0 interface add wlan0 type managed
sudo ifconfig wlan0 up

Raspberry PI GPIO pins (input and output python programming)

Linux Most Used Commands 2nd-Page



"ejabberd xmpp webserver 

Control mounting a file system

You can have more control on mounting a file system like /home and /tmp partitions
mount  -o remount, rw /


How to add library path in linux, so that it would be visible during binary run time:


$ LD_LIBRARY_PATH = /usr/local/lib
$ export LD_LIBRARY_PATH



How to use ctags after running cscope 

1. in /etc/vim/vimrc, add the below
"
" This plugin has been added to enable ctags, after cscope is run
"
if filereadable("/etc/vim/cscope_plugin")
  source /etc/vim/cscope_plugin
endif

2. in /etc/vim/vimrc, add the below
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
" CSCOPE settings for vim
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
"
" This file contains some boilerplate settings for vim's cscope interface,
" plus some keyboard mappings that I've found useful.
"
" USAGE:
" -- vim 6:     Stick this file in your ~/.vim/plugin directory (or in a
"               'plugin' directory in some other directory that is in your
"               'runtimepath'.
"
" -- vim 5:     Stick this file somewhere and 'source cscope.vim' it from
"               your ~/.vimrc file (or cut and paste it into your .vimrc).
"
" NOTE:
" These key maps use multiple keystrokes (2 or 3 keys).  If you find that vim
" keeps timing you out before you can complete them, try changing your timeout
" settings, as explained below.
"
" Happy cscoping,
""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""


" This tests to see if vim was configured with the '--enable-cscope' option
" when it was compiled.  If it wasn't, time to recompile vim...
if has("cscope")

    """"""""""""" Standard cscope/vim boilerplate

    " use both cscope and ctag for 'ctrl-]', ':ta', and 'vim -t'
    set cscopetag

    " check cscope for definition of a symbol before checking ctags: set to 1
    " if you want the reverse search order.
    set csto=0

    " add any cscope database in current directory
    if filereadable("cscope.out")
        cs add cscope.out
    " else add the database pointed to by environment variable
    elseif $CSCOPE_DB != ""
        cs add $CSCOPE_DB
    endif

    " show msg when any other cscope db added
    set cscopeverbose


    """"""""""""" My cscope/vim key mappings
    "
    " The following maps all invoke one of the following cscope search types:
    "
    "   's'   symbol: find all references to the token under cursor
    "   'g'   global: find global definition(s) of the token under cursor
    "   'c'   calls:  find all calls to the function name under cursor
    "   't'   text:   find all instances of the text under cursor
    "   'e'   egrep:  egrep search for the word under cursor
    "   'f'   file:   open the filename under cursor
    "   'i'   includes: find files that include the filename under cursor
    "   'd'   called: find functions that function under cursor calls
    "
    " Below are three sets of the maps: one set that just jumps to your
    " search result, one that splits the existing vim window horizontally and
    " diplays your search result in the new window, and one that does the same
    " thing, but does a vertical split instead (vim 6 only).
    "
    " I've used CTRL-\ and CTRL-@ as the starting keys for these maps, as it's
    " unlikely that you need their default mappings (CTRL-\'s default use is
    " as part of CTRL-\ CTRL-N typemap, which basically just does the same
    " thing as hitting 'escape': CTRL-@ doesn't seem to have any default use).
    " If you don't like using 'CTRL-@' or CTRL-\, , you can change some or all
    " of these maps to use other keys.  One likely candidate is 'CTRL-_'
    " (which also maps to CTRL-/, which is easier to type).  By default it is
    " used to switch between Hebrew and English keyboard mode.
    "
    " All of the maps involving the <cfile> macro use '^<cfile>$': this is so
    " that searches over '#include <time.h>" return only references to
    " 'time.h', and not 'sys/time.h', etc. (by default cscope will return all
    " files that contain 'time.h' as part of their name).


    " To do the first type of search, hit 'CTRL-\', followed by one of the
    " cscope search types above (s,g,c,t,e,f,i,d).  The result of your cscope
    " search will be displayed in the current window.  You can use CTRL-T to
    " go back to where you were before the search.
    "

    nmap <C-\>s :cs find s <C-R>=expand("<cword>")<CR><CR>
    nmap <C-\>g :cs find g <C-R>=expand("<cword>")<CR><CR>
    nmap <C-\>c :cs find c <C-R>=expand("<cword>")<CR><CR>
    nmap <C-\>t :cs find t <C-R>=expand("<cword>")<CR><CR>
    nmap <C-\>e :cs find e <C-R>=expand("<cword>")<CR><CR>
    nmap <C-\>f :cs find f <C-R>=expand("<cfile>")<CR><CR>
    nmap <C-\>i :cs find i ^<C-R>=expand("<cfile>")<CR>$<CR>
    nmap <C-\>d :cs find d <C-R>=expand("<cword>")<CR><CR>


    " Using 'CTRL-spacebar' (intepreted as CTRL-@ by vim) then a search type
    " makes the vim window split horizontally, with search result displayed in
    " the new window.
    "
    " (Note: earlier versions of vim may not have the :scs command, but it
    " can be simulated roughly via:
    "    nmap <C-@>s <C-W><C-S> :cs find s <C-R>=expand("<cword>")<CR><CR>

    nmap <C-@>s :scs find s <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@>g :scs find g <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@>c :scs find c <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@>t :scs find t <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@>e :scs find e <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@>f :scs find f <C-R>=expand("<cfile>")<CR><CR>
    nmap <C-@>i :scs find i ^<C-R>=expand("<cfile>")<CR>$<CR>
    nmap <C-@>d :scs find d <C-R>=expand("<cword>")<CR><CR>


    " Hitting CTRL-space *twice* before the search type does a vertical
    " split instead of a horizontal one (vim 6 and up only)
    "
    " (Note: you may wish to put a 'set splitright' in your .vimrc
    " if you prefer the new window on the right instead of the left

    nmap <C-@><C-@>s :vert scs find s <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@><C-@>g :vert scs find g <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@><C-@>c :vert scs find c <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@><C-@>t :vert scs find t <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@><C-@>e :vert scs find e <C-R>=expand("<cword>")<CR><CR>
    nmap <C-@><C-@>f :vert scs find f <C-R>=expand("<cfile>")<CR><CR>
    nmap <C-@><C-@>i :vert scs find i ^<C-R>=expand("<cfile>")<CR>$<CR>
    nmap <C-@><C-@>d :vert scs find d <C-R>=expand("<cword>")<CR><CR>


    """"""""""""" key map timeouts
    "
    " By default Vim will only wait 1 second for each keystroke in a mapping.
    " You may find that too short with the above typemaps.  If so, you should
    " either turn off mapping timeouts via 'notimeout'.
    "
    "set notimeout
    "
    " Or, you can keep timeouts, by uncommenting the timeoutlen line below,
    " with your own personal favorite value (in milliseconds):
    "
    "set timeoutlen=4000
    "
    " Either way, since mapping timeout settings by default also set the
    " timeouts for multicharacter 'keys codes' (like <F1>), you should also
    " set ttimeout and ttimeoutlen: otherwise, you will experience strange
    " delays as vim waits for a keystroke after you hit ESC (it will be
    " waiting to see if the ESC is actually part of a key code like <F1>).
    "
    "set ttimeout
    "
    " personally, I find a tenth of a second to work well for key code
    " timeouts. If you experience problems and have a slow terminal or network
    " connection, set it higher.  If you don't set ttimeoutlen, the value for
    " timeoutlent (default: 1000 = 1 second, which is sluggish) is used.
    "
    "set ttimeoutlen=100

   set cscopeverbose

endif