Kalanand's May 2015 Log

April 2015

June 2015

May 4th

Grep options revisited

To exclude lines containing a certain word


  grep -v "unwanted_word" file | grep XXXXXXXX

Use grep --exclude/--include syntax to not grep through certain files
```
  grep XXXXXXXX -r --include="*.{cpp,h}" rootdir
```
The syntax for --exclude is identical.
To grep a file but show several surrounding lines, use -B num to set how many lines before the match and -A num for the number of lines after the match
```
  grep -B 3 -A 2 XXXXXXXX README.txt
```
To show the same amount of lines before and after the match, use -C num:
```
  grep -C 3 XXXXXXXX README.txt
```
To count occurrence of a word in a file
```
  grep -c "Error" logfile.txt
```
Grep command option to display lines numbers
```
  grep -n "Error" logfile.txt
```

To append a line after a search result


  grep "import" test.py | sed '/$/ a\Line to be added'

Good grep options to search recursively and ignore binary files in the path:
```
  grep -nrsI "query"
```

May 8th

To git undo all uncommitted changes:


  git reset
  git checkout .

I can also revert uncommitted changes only to particular file or directory:


  git checkout [some_dir|file.txt]

This will remove all local untracked files, so only git tracked files remain:


  git clean -fdx

May 12th

To keep other people's changes intact while modifying files in a common branch, here is the workflow to commit


  git commit -m "my changes"
  git pull --rebase
  git push

May 15th

To start bluetooth on mac (OSX 10.10.X) from commandline


  sudo kextunload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport
  sudo kextload -b com.apple.iokit.BroadcomBluetoothHostControllerUSBTransport

Go to April's log

Last modified: Fri May 15 16:50:00 PDT 2015