Size change after file writing


#1

Hi all,

I write a small script to read old files and write to new files. Either
reading line by line or whole file at once then I ask Ruby to write to
new files. The new file is much smaller than the old one. I also find
that the new file losses many information. How to explain this?

Thanks,

Li

#################script-1 read file line by line and write to a new file
path=‘C:\Allo12-Y2’
file_names=[]

Dir.open(path).each do|f|
file_names<<path+"\#{f}" unless f=~/^..*$/
end

file_names.each do|f|
new_file=File.open("#{f}b",‘w’)
File.open(f,‘r’) do|file|
file.each_line{|line|new_file.print line }
end
end

###################sctript-2 read whole file and write to a new file

path=‘C:\Allo12-Y2’
file_names=[]

Dir.open(path).each do|f|
file_names<<path+"\#{f}" unless f=~/^..*$/
end

file_names.each do|f|
file=File.open(f,‘r’) #open file for read
new_file=File.open("#{f}b",‘w’)#open file for write
new_file.print file.read #write old file to new file
end

size in old file: AlloY2.001 is 609kb

size in new file: AlloY2.001b  is 47bk

#2

Hi,

At Tue, 31 Jul 2007 03:50:24 +0900,
Li Chen wrote in [ruby-talk:262503]:

I write a small script to read old files and write to new files. Either
reading line by line or whole file at once then I ask Ruby to write to
new files. The new file is much smaller than the old one. I also find
that the new file losses many information. How to explain this?

Use “rb” and “wb” mode for binary files, or better, use FileUtils.cp.


#3

Nobuyoshi N. wrote:

Use “rb” and “wb” mode for binary files, or better, use FileUtils.cp.

Thank you very much and they work well.

Li