Sunday, October 17, 2010

How to delete a line which contain matching text line using vim?

I have already added a blog post with a tip for deleting all the matching lines for a matching patern. But this is some thing similar still it is easy after you seached for a text. ie., first search the pattern by "/" and the execute the command -
:g//d
This will delete all the lines with matching patterns. Tested in linux and also in windows.

Sunday, October 3, 2010

How to find number of matches in gvim

It is a easy tip to find the number of matching for the given pattern. Just search and replace it with any thing and see the success message given by vim. It will say "42 substitutions on 21 lines". And now undo changes. Thats it.

Sunday, September 19, 2010

How to find and replace with a new line character in windows gvim?

How to find and replace with a new line character in windows gvim?

It is very easy to find and replace with a new line in windows gvim.  In linux EOL ie., "End Of Line"

character will be "\n" but in windows it is "\r\n".   "\r" character is called as carriage return. Just visualize

old type writer machine carriage return. Now when it comes to find and replace with a new line using

windows is by the following steps,

1)Go to command mode by pressing "Esc" key.
2)Find and replace with a carriage return instead of a new line character. ie.,

:s/SearchText/\r/gc


For linux users, find and replace with a new line. ie.,

:s/SearchText/\n/gc

How to start another batch file in separate process?

Consider a usecase like when you trying to start a apache/tomcat server using a batch file.  After starting the server the batch file will stop thare. Meaning if you have the following in a batch file a.bat,

a.bat:

call c:\Installs\Tomact\bin\run.bat
time
unzip a.zip


then the command unzip and time will never executed. In that case starting a new command prompt and call those command via another batch file is possible and it is easy.

Split the above batch file into two batch files namely a.bat and b.bat with content as follows,

a.bat:

call c:\Installs\Tomact\bin\run.bat


b.bat:


time

unzip a.zip



Now write a another batch file with name c.bat as follows,

c.bat:

start call a.bat
start call b.bat

Now running the c.bat file will run both the batch files will run in separate process and all the commands are executed.

How to delete a line which contain matching text line using vim?

It is easy to delete all lines which have matching text at one shot.  For that you have to change the mode to command by presssing "Esc" key.Then type

:g/match text/d

thats it. All the lines which contain the "match text" will be deleted. This is tested with windows gvim.

Wednesday, August 25, 2010

error: 'Access denied for user 'root'@'localhost' (using password: NO)'

error: 'Access denied for user 'root'@'localhost' (using password: NO)'
Some of us come ac crossed this error when we try connecting Mysql  using no password. ie., when we connect  the mysql by the command "mysql -u root" . When we installing mysql in windows it will ask root password for creating my.ini file. After configuring root password when ever you connect the mysql you should use the command "mysql -u root -p" and enter the password when prompted.  


This will create head aches when you connect mysql through java driver using connection string with out password in a development environment.  To over come this, just reset the password to empty string by using the following three steps/commands - 

  1. UPDATE mysql.user SET Password=PASSWORD('') WHERE User='root';
  2. grant all privileges on *.* to root;
  3. FLUSH PRIVILEGES;

How to password protect a text file using vim?

I heard this tip very recently. For password protecting a file(may be a text file contains some secure password) using vim just open it using "x" option. ie., vim -x <filename>. Or you can do this in some other way while saving it using :X instead of :w

How to enable visual block mode in gvim


This post is for friends who LEARNED vim in linux machine and now using a windows gvim. For friends who used with Linux vim will know "ctrl+v" enables visual block mode. But this key combinations are used to paste the clipboard contents in windows gvim. So, how to enable that visual block mode in windows gvim? It is easy :) press "ctrl+q" thats it. Now don't forget to hold shift key to select block of text for editing.

How to remove end of line using vim/gvim

I was just wondering how to remove all the end of line "\n" or "\n\r" characters and make the entire content into one line.  It is very simple. Go to command mode by pressing the escape key and press "shift + j".  Okay if you want this to be done by a search and replacing command then type :%s/\n//gc in command mode.

How to remove empty lines usgin gvim in windows/Linux

I am searching for this in the internet but with no luck :( And some what managed to make it work. So i just post it for the sake of people who search for deleting or removing blank or empty lines from a file. I tested this on gvim in windows machine and also vim in linux machine.

Steps:

  1. Go to command mode by pressing esc.
  2. Then type - ":%s/^[\ \t]*\n//g" with out quotes. :)