Showing posts with label linux. Show all posts
Showing posts with label linux. Show all posts

Tuesday, 19 April 2016

Using iconv to change character encodings


Introduction

iconv is used for character set conversion facility. With this command, you can turn a string represented by a local character set into the one represented by another character set, which may be the Unicode character set. Supported character sets depend on the iconv implementation of your system. Note that the iconv function on some systems may not work as you expect. In such case, it'd be a good idea to install the » GNU libiconv library. It will most likely end up with more consistent results.

Detail
The basic command is:
iconv -f old-encoding -t new-encoding file.txt > newfile.txt

You can get a list of supported encodings with (that's a lower-case L, not a one):
iconv -l

Example

iconv -f ISO-8859-1 -t UTF8 sample.txt > sample.txt

It is converting from ISO_8859-1 to UTF8.

Resources



Tuesday, 1 March 2016

Breif on SCP Commands

What is Secure Copy?

scp allows files to be copied to, from, or between different hosts. It uses ssh for data transfer and provides the same authentication and same level of security as ssh.

Examples

Copy the file "foobar.txt" from a remote host to the local host

    $ scp your_username@remotehost.edu:foobar.txt /some/local/directory

Copy the file "foobar.txt" from the local host to a remote host

    $ scp foobar.txt your_username@remotehost.edu:/some/remote/directory

Copy the directory "foo" from the local host to a remote host's directory "bar"

    $ scp -r foo your_username@remotehost.edu:/some/remote/directory/bar

Copy the file "foobar.txt" from remote host "rh1.edu" to remote host "rh2.edu"

    $ scp your_username@rh1.edu:/some/remote/directory/foobar.txt \
    your_username@rh2.edu:/some/remote/directory/

Copying the files "foo.txt" and "bar.txt" from the local host to your home directory on the remote host

    $ scp foo.txt bar.txt your_username@remotehost.edu:~

Copy the file "foobar.txt" from the local host to a remote host using port 2264

    $ scp -P 2264 foobar.txt your_username@remotehost.edu:/some/remote/directory

Copy multiple files from the remote host to your current directory on the local host

    $ scp your_username@remotehost.edu:/some/remote/directory/\{a,b,c\} .
    $ scp your_username@remotehost.edu:~/\{foo.txt,bar.txt\} .

scp Performance

By default scp uses the Triple-DES cipher to encrypt the data being sent. Using the Blowfish cipher has been shown to increase speed. This can be done by using option -c blowfish in the command line.
    $ scp -c blowfish some_file your_username@remotehost.edu:~
It is often suggested that the -C option for compression should also be used to increase speed. The effect of compression, however, will only significantly increase speed if your connection is very slow. Otherwise it may just be adding extra burden to the CPU. An example of using blowfish and compression:


Tuesday, 19 January 2016