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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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Set Up Default Password for Postgres User

 Upon installing postgres, there is no password for Postgres User

This is the way to set up default password for Postgres User in Linux

  1. Open terminal
  2. Type: sudo -u postgres psql <-p portNo> eg sudo -u postgres psql -p 5433 or sudo -u postgres psql for default port 5432
  3. Type: postgres=# ALTER USER postgres PASSWORD '<your desired password>';
  4. Type: \q to exit postgres and return back to terminal login
DONE!

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If you have any doubts, please let me know.

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