# Problem renaming files **URL:** \ **Category:** Ruby\ **Created:** [May 11, 2010, 5:10am UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385 "2010-05-11T05:10:20Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![jacob480](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/d9b06d/32.png) [@jacob480](https://www.ruby-forum.com/u/jacob480)\ **Post date:** [May 11, 2010, 5:10am UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385/1 "2010-05-11T05:10:20Z")
Hi Everyone, Im new to ruby and am having a hard time with something Im working on. I want to write a script that takes file names as arguments, then uses gets to get two values, and then renames the files based on those values. example: I want to rename mulitple files, removing the build number, and replacing it with another number. engine.105 -\> rename to engine.8 Anyways, so right now Im just working on doing this with one file at a time. I realize this could be done without a script, but I want to end up doing this with multiple files at once. My script is probably not the most efficient way either, but I’d just like to know what Im doing wrong with how Im doing it. Just so I can learn… Below is the code… I run the file as: ruby c.rb engine.105 I then enter the build number which is 105 Next I enter the version number I want to replace the build number with which is 5 The following is what I get: c.rb:14:in `rename’: No such file or directory - engine.5 or 5 (Errno::ENOENT) from c.rb:14 ===================== #!/usr/bin/env ruby # Filename arguments file\_names = ARGV.dup.to\_s # Have user input build number to be removed puts “Please enter the build number you wish to be removed from the file” build\_number = STDIN.gets.chomp.to\_s # Have user input version number to be appended to file name puts “Please enter the version number you wish to be appended” version\_number = STDIN.gets.chomp.to\_s # Rename file replacing build number with version number File.rename(file\_names, file\_names[build\_number]= version\_number) puts “done!” ---
**Author:** ![jacob480](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/d9b06d/32.png) [@jacob480](https://www.ruby-forum.com/u/jacob480)\ **Post date:** [May 11, 2010, 4:27pm UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385/2 "2010-05-11T16:27:09Z")
Jesús Gabriel y Galán wrote: > On Tue, May 11, 2010 at 5:10 AM, Jacob D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > I want to rename mulitple files, removing the build number, and > > Below is the code… I run the file as: > > (Errno::ENOENT) > > > > # Have user input build number to be removed > > > > puts “done!” > > There are two problems here. The first one is that > file\_names[build\_number] = version will return the right hand side > expression, not the new value of the string, so you will be passing a > “5” to the rename method, not “engine.5”. The second is that by > calling []= on file\_names you are changing the object referenced by > file\_names, not making a new one, so you are passing “engine.5” as the > first argument to rename. Try this instead: > > # Rename file replacing build number with version number > > new\_name = file\_names.dup > new\_name[build\_number] = version\_number > File.rename(file\_names, new\_name) > > Also, when you change things to receive multiple file names as > arguments to your script, you should probably change this line: > > file\_names = ARGV.dup.to\_s > > because that will join all the file names into a single string, which > is not what you want, I think. > > Jesus. Awesome! Yeap that worked! I see where I was making the mistakes last night. I guess its good to step away from it for a bit everyonce in a while. So, I should remove the .to\_s so that it will populate the multiple names into an array correct? Thanks!!! Jacob ---
**Author:** ![jacob480](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/d9b06d/32.png) [@jacob480](https://www.ruby-forum.com/u/jacob480)\ **Post date:** [May 11, 2010, 8:42am UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385/3 "2010-05-11T08:42:45Z")
On Tue, May 11, 2010 at 5:10 AM, Jacob D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > I want to rename mulitple files, removing the build number, and > Below is the code… I run the file as: > (Errno::ENOENT) > > # Have user input build number to be removed > > puts “done!” There are two problems here. The first one is that file\_names[build\_number] = version will return the right hand side expression, not the new value of the string, so you will be passing a “5” to the rename method, not “engine.5”. The second is that by calling []= on file\_names you are changing the object referenced by file\_names, not making a new one, so you are passing “engine.5” as the first argument to rename. Try this instead: # Rename file replacing build number with version number new\_name = file\_names.dup new\_name[build\_number] = version\_number File.rename(file\_names, new\_name) Also, when you change things to receive multiple file names as arguments to your script, you should probably change this line: file\_names = ARGV.dup.to\_s because that will join all the file names into a single string, which is not what you want, I think. Jesus. ---
**Author:** ![jacob480](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/d9b06d/32.png) [@jacob480](https://www.ruby-forum.com/u/jacob480)\ **Post date:** [May 11, 2010, 4:42pm UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385/4 "2010-05-11T16:42:48Z")
On Tue, May 11, 2010 at 4:27 PM, Jacob D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > file\_names[build\_number] = version will return the right hand side > > File.rename(file\_names, new\_name) > > Awesome! Yeap that worked! I see where I was making the mistakes last > night. I guess its good to step away from it for a bit everyonce in a > while. > > So, I should remove the .to\_s so that it will populate the multiple > names into an array correct? Yes, if you do file\_names = ARGV.dup you get an array of file names. Then you can iterate through that array doing the operation to each of them: # Have user input build number to be removed puts “Please enter the build number you wish to be removed from the file” build\_number = STDIN.gets.chomp.to\_s # Have user input version number to be appended to file name puts “Please enter the version number you wish to be appended” version\_number = STDIN.gets.chomp.to\_s # Rename each file replacing build number with version number file\_names.each do |file\_name| new\_name = file\_name.dup new\_name[build\_number] = version\_number File.rename(file\_name, new\_name) end puts “done!” something like that. Jesus. ---
**Author:** ![jacob480](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/d9b06d/32.png) [@jacob480](https://www.ruby-forum.com/u/jacob480)\ **Post date:** [May 11, 2010, 5:04pm UTC](https://www.ruby-forum.com/t/problem-renaming-files/188385/5 "2010-05-11T17:04:27Z")
2010/5/11 Jesús Gabriel y Galán [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid): > On Tue, May 11, 2010 at 4:27 PM, Jacob D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > > Jesús Gabriel y Galán wrote: > > > > > On Tue, May 11, 2010 at 5:10 AM, Jacob D. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > > So, I should remove the .to\_s so that it will populate the multiple > > names into an array correct? > > Yes, if you do > > file\_names = ARGV.dup > > you get an array of file names. Then you can iterate through that > array doing the operation to each of them: You do not even need to #dup because ARGV _is_ an Array already. $ ruby19 -e ‘p ARGV.class’ Array > # Have user input build number to be removed > > puts “Please enter the build number you wish to be removed from the > file” > build\_number = STDIN.gets.chomp.to\_s > > # Have user input version number to be appended to file name > > puts “Please enter the version number you wish to be appended” > version\_number = STDIN.gets.chomp.to\_s #to\_s is not needed but checking the input is probably also a good idea. You could simply do version\_number = STDIN.gets.chomp Integer(version\_number) # will throw if not numeric Kind regards robert