sed variation in MacOSX with space and newline

Question

Need to replace a comma followed by space with a newline

On LINUX I see people posting examples such as

sed 's/,\s/\n/g' textfile

Whereas in MacOSX this doesn't work but the following does

sed 's/, /\
/g' testfile 

The space as in real space and the newline character is an actual backslash with a newline 'entered'

What am i doing wrong ?

Answer 1

On OSX you can do:

sed -i.bak 's/, /\'$'\n''/g' file

Or this:

sed -i.bak $'s/, /\\\n/g' file

As per man bash :

 Words  of  the  form  $'string'  are  treated specially.  The word expands to string, 
 with backslash-escaped characters replaced as specified by the ANSI C standard. 
 Backslash escape sequences, if present, are decoded as follows:
          \a     alert (bell)
          \b     backspace
          \e     an escape character
          \f     form feed
          \n     new line
          \r     carriage return
          \t     horizontal tab
          \v     vertical tab
          \\     backslash
          \'     single quote
          \nnn   the eight-bit character whose value is the octal value nnn
                 (one to three digits)
          \xHH   the eight-bit character whose value is the hexadecimal value HH
                 (one or two hex digits)
          \cx    a control-x character