You've reinvented one of the most common questions asked here. And you've already implemented one of the most common solutions. So bonus points for that ;-)

Unfortunately, while there are variations, there isn't really a better way of performing this trick. But you could see How do I change one line in a file/delete a line in a file/insert a line in the middle of a file/append to the beginning of a file? for further comments

--
Tommy
Too stupid to live.
Too stubborn to die.

See perlrun

-Bird

This is not quite what the OP asked. From perlrun:



-i[extension]
            specifies that files processed by the `<>' construct
            are to be edited in-place.  It does this by renaming
            the input file, opening the output file by the
            original name, and selecting that output file as the
            default for print() statements.  The extension, if
            supplied, is used to modify the name of the old file
            to make a backup copy, following these rules:
[download]

Meaning that -i basically does the same 'trick': open for read, edit, write back.

This is not quite what the OP asked.

How? The original post asked for a way to edit a file in place, which this is. This is not the same solution that the original post presented, because it does not entail reading the entire file into an array, then writing it back out. It allows for line by line editing, as well as giving an option for renaming the original. Even if this was the same solution as the original, it's a much more concise form of it, which means you could write a quick one-liner using this version, as opposed to writing out a whole script using the alternative.

-Bird

I hadn't thought about the backup aspect of the edit process. I think that will be useful. Thanks for your comments.

0000000   #   !   /   u   s   r   /   l   o   c   a   l   /   b   i   
+n
        043 041 057 165 163 162 057 154 157 143 141 154 057 142 151 15
+6
0000020   /   p   e   r   l       -   w  \n   u   s   e       s   t   
+r
        057 160 145 162 154 040 055 167 012 165 163 145 040 163 164 16
+2
0000040   i   c   t   ;  \n   p   r   i   n   t       "   H   e   l   
+l
        151 143 164 073 012 160 162 151 156 164 040 042 110 145 154 15
+4
0000060   o       W   o   r   l   d   \   n   "   ;  \n
        157 040 127 157 162 154 144 134 156 042 073 012
0000074
[download]

Also, this is just how text files are implemented on one operating system (Unix). Others may use different line terminators, or implement in a completely diferent way, such as VMS, which stores the text file as a series of variable length records. Anything which relies of the Unix representation will potentially be non-portable.