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82 lines
1.9 KiB
82 lines
1.9 KiB
2 years ago
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## custom-ls
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### Instructions
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Create the script `custom-ls.sh` which will create an alias `custom-ls`.
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The alias `custom-ls`:
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- shows the file details in long list format.
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- does not list group information.
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- does not ignore entries starting with `.`.
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- prints the allocated size of each file, in blocks.
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- sorts by file size, largest first.
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Expected behavior:
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```console
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$ custom-ls
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error: command not found: custom-ls
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$ ./custom-ls.sh
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$ custom-ls .
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total ...
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7784 -rw-r--r-- 1 <user> 3983261 Dec 17 22:02 .file1 # just an example
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3064 -rw-r--r-- 1 <user> 1566444 Dec 17 22:12 file2 # just an example
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$
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```
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### Hints
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An alias is a shortcut that references a command. An alias replaces a string that invokes a command in the Linux shell with another user-defined string.
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`alias` command instructs the shell to replace one string with another string while executing the commands.
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```console
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$ alias testcmd="echo 01school"
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$ testcmd
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01school
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$ alias
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testcmd='echo 01school'
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<...>
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$
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```
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> However, this update alias gets removed after closing the working environment.
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To create and add aliases permanently to your bash shell on Linux and Unix-like systems:
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1- Edit the `~/.bashrc`:
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```console
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vi ~/.bashrc
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# or #
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nano ~/.bashrc
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```
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2- Append your bash alias, For example append:
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```console
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alias testcmd="echo 01school"
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```
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3- Save and close the file.
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4- Activate alias
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```console
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source ~/.bashrc
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```
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`unalias` unalias removes each alias name from the current shell execution environment.
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```console
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$ alias
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testcmd='echo 01school'
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<...>
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$ unalias testcmd
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$ alias
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<...>
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$
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```
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> You have to use Man or Google to know more about commands flags, in order to solve this exercise!
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> Google and Man will be your friends!
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### References
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[alias command in linux with examples.](https://www.geeksforgeeks.org/alias-command-in-linux-with-examples/)
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[man ls.](https://man7.org/linux/man-pages/man1/ls.1.html)
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