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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...
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How do I increased Swap Memory of Ubuntu OS using terminal from 1GB to 7GB

 Hi, I have increase my Ubuntu OS swap memory from 1GB to 7GB by adding additional 6GB space to swap. Process which I followed is as follows:

1> Check previous Swap Memory:

cat /proc/swaps

2> Check previous Swap Memory:

swapon

3> Check previous Swap Memory:

free

4> Create new Swap Memory:

sudo dd if=/dev/zero of=/newswap bs=1024 count=6M

5> Set permissions for new Swap Memory

sudo chmod 0600 /newswap

6> Bake new swap:

sudo mkswap /newswap

7> Turn on new swap:

sudo swapon /newswap

8> Check new Swap Memory:

swapon

9> Modify /etc/fstab file by adding following lines at the end

/newswap    swap    swap   defaults 0 0

Done!

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If you have any doubts, please let me know.

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