Merge pull request #432 from Aggarwalmansi/improve-linux-guides

Improve and standardize Linux command guides: mkdir, column, cmatrix,…

Author: bobbyiliev

ebook/en/content/035-the-killall-command.md

@@ -19,10 +19,10 @@ killall conky
 # OR
 killall -SIGTERM conky
 # OR
-kilall -15 conky
+killall -15 conky
 ```
 
-I was able to kill Wine ( which are Windows exe files running on Linux ) applications this way too.
+You can also kill Wine processes (Windows executable files running on Linux) this way.
 
 ```sh
 killall TQ.exe
@@ -108,20 +108,20 @@ killall -V, --version
 
 |**Short Flag**   |**Long Flag**   |**Description**   |
 |:---|:---|:---|
-|`-e`|`--exact`|require  an  exact  match for very long names|
+|`-e`|`--exact`|require an exact match for very long names|
 |`-I`|`--ignore-case`|case insensitive process name match|
 |`-g`|`--process-group`|kill process group instead of process|
 |`-y`|`--younger-than`|kill processes younger than TIME|
 |`-o`|`--older-than`|kill processes older than TIME|
-|`-i`|`--interactive`|ask for confirmation before killing|
+|`-i`|`--interactive`|Prompt before killing processes to avoid accidental termination.|
 |`-l`|`--list`|list all known signal names|
 |`-q`|`--quiet`|don't print complaints|
 |`-r`|`--regexp`|interpret NAME as an extended regular expression|
 |`-s`|`--signal SIGNAL`|send this signal instead of SIGTERM|
 |`-u`|`--user USER`|kill only process(es) running as USER|
 |`-v`|`--verbose`|report if the signal was successfully sent|
 |`-w`|`--wait`|wait for processes to die|
-|`-n`|`--ns PID`|match processes that belong to the same namespaces as PID
+|`-n`|`--ns PID`|Match processes belonging to the same namespace as the specified PID.
 |`-Z`|`--context`|REGEXP kill only process(es) having context (must precede other arguments)
 
 ### Related commands

ebook/en/content/058-the-reboot-command.md

@@ -1,6 +1,6 @@
 # The `reboot` Command
 
-The `reboot` command is used to restart a linux system. However, it requires elevated permission using the [sudo](https://github.com/bobbyiliev/101-linux-commands/blob/main/ebook/en/content/051-the-sudo-command.md) command. Necessity to use this command usually arises after significant system or network updates have been made to the system.
+The `reboot` command is used to restart a Linux system. However, it requires elevated permission using the [sudo](https://github.com/bobbyiliev/101-linux-commands/blob/main/ebook/en/content/051-the-sudo-command.md) command. Necessity to use this command usually arises after significant system or network updates have been made to the system.
 
 ## Syntax
 ```
@@ -10,7 +10,7 @@ reboot [OPTIONS...]
 ### Options
 - **–help** : This option prints a short help text and exit.
 - **-halt** : This command will stop the machine.
-- **-w**, **–wtmp-only** : This option only writes wtmp shutdown entry, it do not actually halt, power-off, reboot.
+- **-w**, **–wtmp-only** : This option only writes wtmp shutdown entry, it does not actually halt, power-off, reboot.
 
 ### Examples
 1. Basic Usage. Mainly used to restart without any further details
@@ -22,9 +22,9 @@ However, alternatively the shutdown command with the `-r` option
 $ sudo shutdown -r now
 ```
 
-**Note** that the usage of the reboot, halt and power off is almost similar in syntax and effect. Run each of these commands with –help to see the details.
+**Note** that the usage of the reboot, halt and power off is almost similar in syntax and effect. Run each of these commands with –-help to see the details.
 
-2. The `reboot` command has limited usage, and the `shutdown` command is being used instead of reboot command to fulfill much more advance reboot and shutdown requirements. One of those situations is a scheduled restart. Syntax is as follows
+2. The `reboot` command has limited usage, and the `shutdown` command is being used instead of reboot command to fulfill much more advanced reboot and shutdown requirements. One of those situations is a scheduled restart. Syntax is as follows
 ```
 $ sudo shutdown –r [TIME] [MESSAGE]
 ```
@@ -50,7 +50,8 @@ $ sudo shutdown –c [MESSAGE]
 $sudo shutdown -c "Scheduled reboot cancelled because the chicken crossed the road"
 ```
 
-4. Checking your reboot logs
+4. Shows a history of system reboots
+**Syntax**
 ```
 $ last reboot
 ```

ebook/en/content/064-the-gunzip-command.md

@@ -2,7 +2,7 @@
 
 The `gunzip` command is an antonym command of [`gzip` command](015-the-gzip-command.md). In other words, it decompresses files deflated by the `gzip` command.
 
-`gunzip` takes a list of files on its command line and replaces each file whose name ends with _.gz_, _-gz_, _.z_, _-z_, or *\_z* (ignoring case) and which begins with the correct magic number with an uncompressed file without the original extension. `gunzip` also recognizes the special extensions *.tgz* and *.taz* as shorthands for *.tar.gz* and  *.tar.Z*  respectively.
+"`gunzip` takes a list of files as arguments. It replaces each file whose name ends with `.gz`, `-gz`, `.z`, `-z`, or `_z` (case-insensitive) and which begins with the correct magic number with an uncompressed file, removing the original extension."
 
 ### Examples:
 
@@ -12,13 +12,13 @@ The `gunzip` command is an antonym command of [`gzip` command](015-the-gzip-comm
 gunzip filename.gz
 ```
 
-2. Recursively uncompress content inside a directory, that match extension (suffix) compressed formats accepted by `gunzip`:
+2. "Recursively uncompress all files inside a directory that match the compressed file formats supported by `gunzip`:"
 
 ```
 gunzip -r directory_name/
 ```
 
-3. Uncompress all files in the current/working directory whose suffix match *.tgz*:
+3. "Uncompress all files in the current working directory whose suffix matches `.tgz`:
 
 ```
 gunzip -S .tgz *
@@ -54,4 +54,8 @@ gunzip [ -acfhklLnNrtvV ] [-S suffix] [ name ...  ]
 ||--synchronous|synchronous output (safer if system crashes, but slower)|
 |-t|--test|test compressed file integrity|
 |-v|--verbose|verbose mode|
-|-V|--version|display version number|
+|-V|--version|display version number|
+
+
+### **Note: gunzip filename.gz is equivalent to gzip -d filename.gz.
+### Warning: Running gunzip without -c deletes the original compressed file by default.

ebook/en/content/162-the-column-command.md

@@ -40,14 +40,23 @@ mount | column -t
 4. Custom Column Separator
 ```bash
 # Format CSV data with custom separator
-echo "Name,Age,City\nJohn,25,NYC\nJane,30,LA" | column -t -s,
+echo -e "Name,Age,City\nJohn,25,NYC\nJane,30,LA" | column -t -s,
+
+Name  Age  City
+John  25   NYC
+Jane  30   LA
+
 ```
 
 5. Left-aligned Table
 ```bash
 # Create a left-aligned table from space-separated data
 ps aux | head -n 5 | column -t -L
 ```
+> **Note:** Options like `-L` and `-R` may not be available in all Linux distributions (mainly GNU `column`).
+
+# Format a file into columns (e.g., data.txt)
+column -t -s, data.txt
 
 ## Additional Information
 - The `column` command is part of the `util-linux` package