Skip to main content

How to use gdb in Ubuntu Terminal

Here's a practical, minimal guide for using GDB in Ubuntu terminal — from launching to setting breakpoints and navigating your code. 🧰 Step 1: Compile with Debug Symbols Use -g and disable optimizations ( -O0 preferred for debugging): bash Copy Edit g++ -g -O0 -o myprog myprog.cpp 🚀 Step 2: Launch GDB bash Copy Edit gdb ./myprog You'll see a (gdb) prompt. 🎯 Step 3: Set Breakpoints You can set breakpoints in three main ways : ✅ a. At a function gdb Copy Edit (gdb) break main ✅ b. At a specific file and line gdb Copy Edit (gdb) break myprog.cpp:42 ✅ c. At a method in a class gdb Copy Edit (gdb) break MyClass::doSomething If the symbol is mangled (C++), GDB usually demangles automatically, especially if compiled with -g . ▶️ Step 4: Run the Program gdb Copy Edit (gdb) run 🧭 Step 5: Navigate Command Meaning next or n Step over current line step or s Step into function call finish Run until current function returns continue or c Continue until...
Post a Comment

How to Add Free SSL Certificate from ZeroSSL int your Java Tomcat / Tomee website?

Assumptions:
1. You are using Linux / Debian Server
2. You are using Compute Engine
3. You are using Google Domains

----------------------------------------------------------------------
Procedure:
1. Set $JAVA_HOME=<path to your java base directory>
2. Set $CATALINA_BASE=<path to your Tomcat / Tomee base directory>

3. Type command: $JAVA_HOME/bin/keytool -genkey -alias <server> -keyalg RSA -keysize <2048> -keystore <path to your keystore file.jks>
 Note: When asked for your first and last name, give your website domain name like www.mohitkrgupta.dev

4. Type command: $JAVA_HOME/bin/keytool -certreq -alias <server> -file <csr.txt> -keystore <path to your keystore file.jks>

This will generate csr.txt key file to be submitted to Certifying Authority (ZeroSSL in this case)

5. Visit ZeroSSL site and copy-pase content of csr.txt and follow processes as mentioned in website to get your SSL keys
6. Your SSL key document will be available from there in .zip format, download and unzip it.
7. It will contain following files:
    certificate.crt, and ca_bundle.crt.
8. Type Command: openssl crl2pkcs7 -nocrl -certfile <certificate.crt> -out <certificate.p7b> -certfile <ca_bundle.crt>
//(you will get certificate.p7b file in this way)
9. Type Command: JAVA_HOME/bin/keytool -import -alias <server> -file <certificate.p7b> -keystore <path to your keystore file.jks>
10. Type Command: sudo nano $CATALINA_BASE/conf/server.xml
11. Provide following lines in server.xml

<Connector port="443" maxHttpHeaderSize="8192" maxThreads="100"
           minSpareThreads="25" maxSpareThreads="75"
           enableLookups="false" disableUploadTimeout="true"
           acceptCount="100" scheme="https" secure="true"
           SSLEnabled="true" clientAuth="false"
           sslProtocol="TLS" keyAlias="server"
           keystoreFile="</home/newmkg/mohitkrgupta.dev.jks>"
           keystorePass="<*************>" />

12. // restart tomc(at/ee) server
13. Check your working https:// website in your domain name

Work Done

Comments

Post a Comment

If you have any doubts, please let me know.

Popular posts from this blog

Ubuntu Notes: Set up autossh as systemd useful-reminder commands

 sudo vim /etc/systemd/system/permanentAutossh.service ======================================== [Unit] Description=Keeps a tunnel to myOciFreeNat open After=network-online.target [Service] User=<username> Environment="AUTOSSH_GATETIME=0" ExecStart=/usr/bin/autossh -M 0 -q -N -o "ServerAliveInterval 60" -o "ServerAliveCountMax 3" -L 4322:127.0.0.1:5432 -i /<ssh_private_key_file_absolute_path> <username>@<ip_address> -p 22 [Install] WantedBy=multi-user.target ======================================== sudo systemctl daemon-reload sudo systemctl enable permanentAutossh sudo systemctl start permanentAutossh ================== sudo systemctl daemon-reload sudo systemctl restart permanentAutossh sudo systemctl status permanentAutossh ====================== sudo systemctl stop permanentAutossh sudo systemctl disable permanentAutossh sudo rm /etc/systemd/system/permanentAutossh.service
Post a Comment
Read more

syslog cpp programming: learning using chatGcp

  Introduction to Syslog C++ August 27, 2024 This conversation may reflect the link creator’s personalized data, which isn’t shared and can meaningfully change how the model responds. You said: I am new to syslog in cpp programming n just starting. Can you teach me ChatGPT said: ChatGPT Sure! syslog is a standard for logging system messages in Unix-like operating systems. It provides a way to send log messages to the system log, which can then be collected and analyzed by various tools. Here's a basic guide to get you started with syslog in C++: 1. Include the Necessary Header To use syslog , you need to include the syslog.h header: cpp Copy code # include <syslog.h> 2. Open the Connection to syslog Before sending log messages, you need to open a connection to the syslog system. This is typically done at the start of your program: cpp Copy code openlog ( "your_program_name" , LOG_PID | LOG_CONS, LOG_USER); "your_program_name" : A string representing ...
Post a Comment
Read more

Ubuntu - C++ Notes: Install & update boost c++ library from git (may contain some error in process mentioned below)

 Boost C++ Library Installation from git in ubuntu: 1. create a directory named boost in your desired location and go to that directory mkdir boost;cd boost; 2. clone boost recursively from git using command git clone --recursive https://github.com/boostorg/boost.git 3. cd boost; sudo ./bootstrap.sh; 4. sudo ./b2; 5. sudo ./b2 install; DONE! --------------------------- Boost C++ Library Update Verson from git in Ubuntu: 1. go to gitDownloads/boost directory cd gitDownloads/boost; 2. git pull; 3. git submodule update --recursive; 4. cd boost; sudo ./bootstrap.sh; 5. sudo ./b2; 6. sudo ./b2 install; DONE!
Post a Comment
Read more