Test IMAP with telnet IMAP connection theory The first thing any client needs to do is to make a connection to the remote imap server on a specific port. These ports can vary, but default port for plaintext imap service is 143 , and for encrypted (SSL/TLS) imap service is default port 993 . You can use for plaintext imap connection a telnet utility, or for encrypted imap service you can use openssl s_client command. Networking Linux
Linux Command Line Tips and Tricks Text Editing For mostly all examples we use sed utility with substitution command. The syntax is pretty simple: sed -i 's/SEARCH-WORD/REPLACMENT-WORD/gI' input # or for regular expressions: sed -i 's/SEARCH-REGEXP/REPLACMENT-WORD/gi' input The -i option edit and update text file in place. For piped input from another utility it is not necessary The / are delimiters between words or regexp. sed -i 's/SEARCH-REGEXP/REPLACMENT-WORD/gI' - I flag make search case insensitive sed -i 's/SEARCH-REGEXP/REPLACMENT-WORD/gI' - for text files input use g flag to make search global across the whole file print first N chars We want print first N chars. Linux
SED Tutorial - how replace or substitute file contents How replace or substitute text in SED text stream editor Linux Linux Utilities
cut command in linux with examples The cut command is a command-line utility for cutting sections from each line of a file. It writes the result to the standard output. It’s worth noting that it does not modify the file, but only works on a copy of the content. Although typically the input to a cut command is a file, we can pipe the output of other commands and use it as input. It can be used to cut parts of a line by byte position, character and field. Linux Linux Utilities
Arpwatch - monitor mac addresses change Arpwatch Arpwatch is an open source computer software program that helps you to monitor Ethernet traffic activity (like Changing IP and MAC Addresses) on your network and maintains a database of ethernet/ip address pairings. It produces a log of noticed pairing of IP and MAC addresses information along with a timestamps, so you can carefully watch when the pairing activity appeared on the network. It also has the option to send reports via email to an network administrator when a pairing added or changed. Networking Linux Security
Awk BuiltIn Variables The following is a list of variables that awk sets automatically on certain occasions in order to provide information to your program. The variables that are specific to gawk are marked with a pound sign (#). These variables are gawk extensions. In other awk implementations or if gawk is in compatibility mode (see section Command-Line Options ), they are not special. VARIABLE NAME DESCRIPTION FS input field separator variable OFS Output Field Separator RS Input Record Separator variable ORS Output Record Separator Variable NR Number of Records NF Number of Fields in a record FILENAME Name of the current input file FNR Number of Records relative to the current input file RLENGTH length of the substring matched by the match() function RSTART first position in the string matched by match() function FS - input field separator variable It represents the (input) field separator and its default value is space. Linux Linux Utilities Bash Development
Awk If Statement In this awk tutorial, let us review awk conditional if statements with practical examples. Normally conditional statement checks the condition, before performing any action. If the condition is true action(s) are performed. Similarly action can be performed if the condition is false. Conditional statement starts with the keyword called "if". Awk supports three different kind of if statement. Awk Simple If statement Awk If-Else statement Awk If-Else-If statement awk If Statement Single Action: Simple If statement is used to check the conditions, if the condition returns true, it performs its corresponding action(s). Linux Linux Utilities Bash Development
YUM Commands for Package Management What is YUM? YUM (Yellowdog Updater Modified) is an open source command-line as well as graphical based package management tool for RPM (RedHat Package Manager) based Linux systems. It allows users and system administrator to easily install, update, remove or search software packages on a systems. It was developed and released by Seth Vidal under GPL (General Public License) as an open source, means anyone can allowed to download and access the code to fix bugs and develop customized packages. Linux
How Pause-Resume any Task or Process in Windows Resource Monitor - resmon.exe is an highly useful tool built-in to Windows to monitor the various resource (CPU, Disk) usage of PC. It’s overshadowed by another similar and commonly known tool, Task Manager although some of its features are superior to the latter. suspend/resume a running task in Windows Open up Resource Monitor. You can search for it in the Start or call it by its pet name resmon Now in the Overview or CPU tab, look for process you want to Pause in the list of running Processes. Windows
Installation of LTE modem into Turris Omnia router Assembly You need a cross-point screwdriver for the assembly. Step 1 Remove the 6 screws using the cross-point screwdriver. Then carefully remove the upper cover of the router. Make sure that thermal conductive rubber will remain sticked to the CPU cooler while removing the cover. If it detaches put it back on the cooler. Step 2 Insert the SIM card into the SIM slot located under one of the mPCIe slots. Networking
Useful tips for Debian based distros Debian bookworm - behavior of more utility has changed I've just ran apt upgrade and apt dist-upgrade and noticed the behavior of more utility has changed. In particular I have to supply -e option in my scripts otherwise it currently presents me with (END) prompt in console. Or when I have alias with more utility, example: alias lf="ls -alFh|more", the output end with (END) prompt in console. Manual says the following: Debian Linux Linux Utilities
How Modify Systemd Unit Files Right Way Location of systemd unit files /lib/systemd/system - The system's copy of unit files are generally kept in this directory. When software installs unit files on the system, this is the location where they are placed by default. /run/systemd/system - Systemd unit files created at run time. This directory takes precedence over the directory with installed service unit files. /etc/systemd/system/ - If you wish to modify the way that a unit functions, the best location to do so is within this directory. Linux
