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Copy specific file and its structure

Description

Suppose the file structure under the directory /tmp/gsl is like following shows(notice that not all sub-directory has Makefile, for example ./block):

.
|-- INSTALL
|-- Makefile
|-- NEWS
|-- ...
|-- blas
|   |-- ChangeLog
|   |-- Makefile
|   |-- TODO
|   |-- blas.c
|   |-- ...
|-- block
|   |-- ChangeLog
|   |-- block.c
|-- bspline
|   |-- Makefile
|   |-- ...
|-- ...

There are many Makefile in different sub-directories and we want to copy those Makefile to home/usrname/gsl. And the result should be like this:

.
|-- Makefile
|-- blas
|   |-- Makefile
|-- bspline
|   |-- Makefile
|-- ...

Question

  • if the target directory already have necessary parent folder for Makefile, like blas, bspline, how to copy?
  • if the target directory don’t have necessary parent folder for Makefile, like blas, bspline, how to copy?

Answer only for question 1

cd /tmp/gsl
# use `find` to find out those file;
# use `sed` to substitute directory name:
# ':' used as substitution delimiter, '&' represent previous matched string -- i.e. whole file path, '\1' as matched content in '()' -- i.e. the directory structure of Makefile;
# and finally use `bash` to execute copy.
find . -name 'Makefile' | sed 's:\(.*\)/Makefile:cp & /home/username/gsl/\1 :' | bash -s

Answer for question 1 & 2

simpler and cleaner.
use --parents flag to create necessary directory for copy.

–parents
Form the name of each destination file by appending to the target
directory a slash and the specified name of the source file. The
last argument given to cp must be the name of an existing
directory. For example, the command:
cp --parents a/b/c existing_dir
copies the file a/b/c to existing_dir/a/b/c, creating any
missing intermediate directories.

cd /tmp/gsl/
# the usage of `xargs -i` is much like for each file path of Makefile, `{}` represent the file path
find .  -name 'Makefile' | xargs -i cp --parents {} /home/usrname/gsl/

复制特定文件及其相关文件结构

假设当前Linux系统的目录/tmp/gsl下的文件结构如下图所示，其中有很多Makefile分散在各个子目录下(但并非每个子目录都存在Makefile，例如block目录下就没有)。

.
|-- INSTALL
|-- Makefile
|-- NEWS
|-- ...
|-- blas
|   |-- ChangeLog
|   |-- Makefile
|   |-- TODO
|   |-- blas.c
|   |-- ...
|-- block
|   |-- ChangeLog
|   |-- block.c
|-- bspline
|   |-- Makefile
|   |-- ...
|-- ...

要求将这些Makefile拷贝到目录/home/usrname/gsl的对应子目录下，使得拷贝后/home/usrname/gsl下的文件如下图所示：

.
|-- Makefile
|-- blas
|   |-- Makefile
|-- bspline
|   |-- Makefile
|-- ...

问题一：
假设/home/usrname/gsl下已经存在blas，bspline等子目录，如何实现？
问题二：
假设/home/usrname/gsl下不存在blas，bspline等子目录，如何实现？

问题1的答案

cd /tmp/gsl
# 使用 `find` 找出Makefile的路径;
# 使用 `sed` 替换路径:
# ':' 作为替换分割符, '&' 代表整个匹配度字符串-- i.e. 整个文件路径, '\1' 代表'()'匹配内容 -- i.e. Makefile路径前缀;
# 最后使用 `bash` 来执行复制.
find . -name 'Makefile' | sed 's:\(.*\)/Makefile:cp & /home/username/gsl/\1 :' | bash -s

问题1 & 2的答案

使用 --parents flag 来创建需要的父目录.

--parents
Form the name of each destination file by appending to the target
directory a slash and the specified name of the source file. The
last argument given to cp must be the name of an existing
directory. For example, the command:
cp --parents a/b/c existing_dir
copies the file a/b/c to existing_dir/a/b/c, creating any
missing intermediate directories.

cd /tmp/gsl/
# `xargs -i` 就像对Makefile的文件路径集合进行循环操作, 而`{}`就像循环变量，代表每一个不同的路径
find .  -name 'Makefile' | xargs -i cp --parents {} /home/usrname/gsl/

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