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To compile a C program in Linux, use gcc; for C++, use g++. Add -o to name the executable, then run it from the current directory with ./:
gcc main.c -o main
./mainFor a C++ source file, use g++ main.cpp -o main followed by ./main. The C++ driver links the standard library automatically.
Compile and run one C or C++ file
C
Open a terminal in the directory containing your source file. If it is named main.c, run:
gcc main.c -o mainThen launch the executable from that directory:
./mainGCC normally handles preprocessing, compilation, assembly, and linking in one invocation. Its -o option sets the output filename. See the GCC overall options manual.
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- Read Before You Buy — No Video Output: These adapters support charging and USB 2.0 data transfer, but cannot transmit video signals. Except for standard USB webcams (which use USB data only), they are not compatible with HDMI/DisplayPort cables, video-capable USB-C hubs, or docking stations with video output.
- Convert USB-A Ports to USB-C: Designed to connect USB-C earphones, cables, flash drives, card readers, and other USB-C accessories to standard USB-A ports. Plug-and-play with no drivers or software required.
- Aluminum Alloy Housing: Built with a sturdy aluminum alloy shell that aids in heat dissipation and protects against daily wear and scratches. Designed to maintain a stable and secure connection.
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- 12-Month Warranty: Backed by a 12-month manufacturer warranty for peace of mind. Designed to meet strict quality control standards for reliable everyday performance.
C++
For a C++ source file named main.cpp, use the C++ compiler driver:
g++ main.cpp -o main
./mainUse g++ rather than gcc for a C++ build. GCC may recognize C++ source suffixes, but the gcc driver does not automatically link the C++ standard library; g++ does. A build using gcc can therefore reach the linking stage and fail with undefined references to C++ library symbols. See the GCC manual’s g++ invocation notes.
Rank #2
- 5-in-1 USB-C Hub: Experience comprehensive connectivity featuring a Power Delivery input, two USB-A 2.0 ports, a USB-A 3.0 port, and an HDMI port. (Note: The USB-C power delivery input port is only for connecting an external wall charger to power your laptop and cannot power peripheral devices.)
- 90W Pass-Through Charging: Achieve optimal charging with 90W pass-through power to your laptop, supported by a total input of 100W, with the hub reserving 10W for operational efficiency. (Note: Wall charger not included.)
- Quick Data Transfers: Accelerate your productivity with rapid data transfers using a high-speed 5Gbps USB 3.0 port and two 480Mbps USB 2.0 ports.
- 4K HDMI Display: Enhance your visual experience with a hub capable of delivering 4K resolution at 30Hz in both mirror and extend modes. Please note that this hub is compatible with MacBook (macOS 12 and newer), Windows 10 and 11, ChromeOS, and laptops equipped with DP Alt Mode and Power Delivery. Note: This device is not compatible with Linux.
- What You Get: Anker USB-C Hub (5-in-1, 4K HDMI), welcome guide, 18-month warranty, and our friendly customer service.
Build a program made of multiple source files
Compile and link in one command
List each source file in the command. The driver compiles them and links them into the named executable:
gcc main.c helper.c -o app
./appFor C++, use g++ for both compilation and linking:
g++ main.cpp helper.cpp -o app
./appInclude every source file needed by the program. If a required file is omitted, the linker may report undefined references to functions or other symbols defined there.
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Rank #3
- Sleek 7-in-1 USB-C Hub: Features an HDMI port, two USB-A 3.0 ports, and a USB-C data port, each providing 5Gbps transfer speeds. It also includes a USB-C PD input port for charging up to 100W and dual SD and TF card slots, all in a compact design.
- Flawless 4K@60Hz Video with HDMI: Delivers exceptional clarity and smoothness with its 4K@60Hz HDMI port, making it ideal for high-definition presentations and entertainment. (Note: Only the HDMI port supports video projection; the USB-C port is for data transfer only.)
- Double Up on Efficiency: The two USB-A 3.0 ports and a USB-C port support a fast 5Gbps data rate, significantly boosting your transfer speeds and improving productivity.
- Fast and Reliable 85W Charging: Offers high-capacity, speedy charging for laptops up to 85W, so you spend less time tethered to an outlet and more time being productive.
- What You Get: Anker USB-C Hub (7-in-1), welcome guide, 18-month warranty, and our friendly customer service.
Compile files separately, then link
Use -c to compile a source file without linking. This produces an object file, which can be linked in a later command:
gcc -c main.c -o main.o
gcc -c helper.c -o helper.o
gcc main.o helper.o -o app
./appFor a C++ program, link with g++ so the C++ standard library is included:
Rank #4
- Dual Converters, Infinite Potential：Includes 2× USB C male to USB A female adapters and 2× USB A male to USB C female adapters. Perfect for a wide range of uses—tablets with Bluetooth keyboards, expand USB ports on macbook, and more. Two different converters for all your daily needs
- Next-Level 10Gbps & 3A Charging: No more slow 480Mbps, this usb to usb c adapter has a transfer speed of up to 10Gbps, allowing you to do more transferring in less time. This usb adapter fits both USB A and USB C charger, supporting up to 3A fast charging
- Upgraded Exquisite Craftsmanship: With an aluminum alloy housing and metal connector, the usbc to usb adapter is extremely durable and sturdy. Rigorously tested to withstand more than 10,000 times of plugging and unplugging, ensuring long-lasting performance
- Broad Compatible: The usb c to usb adapter widely supports all USB C/ USB A devices like laptops, tablets, cellphones, car chargers, and phone chargers. Such as compatible with MacBook Pro/Air 2023/2022, Thunderbolt 4/3 Devices,Apple MagSafe Watch 9/8/7/SE/Ultra, iPad Pro 2022/2021, Samsung Galaxy S23/S20/S10, and iPhone 17/16/15 Pro. Plug and play
- Please Note: To reach 10Gbps speed, keep the cable under 3.3 ft. For USB A Male to USB C adapters, try flipping the USB C connector. USB C Male to USB A adapters support bidirectional 10Gbps transfer within 3.3 ft
g++ -c main.cpp -o main.o
g++ -c helper.cpp -o helper.o
g++ main.o helper.o -o app
./appThe GCC overall options manual describes -c as stopping before the linking stage.
Use Clang instead of GCC
Clang also supports C and C++. Its command-line drivers are clang for C and clang++ for C++:
Best Value
- 5-in-1 Connectivity: Equipped with a 4K HDMI port, a 5 Gbps USB-C data port, two 5 Gbps USB-A ports, and a USB C 100W PD-IN port. Note: The USB C 100W PD-IN port supports only charging and does not support data transfer devices such as headphones or speakers.
- Powerful Pass-Through Charging: Supports up to 85W pass-through charging so you can power up your laptop while you use the hub. Note: Pass-through charging requires a charger (not included). Note: To achieve full power for iPad, we recommend using a 45W wall charger.
- Transfer Files in Seconds: Move files to and from your laptop at speeds of up to 5 Gbps via the USB-C and USB-A data ports. Note: The USB C 5Gbps Data port does not support video output.
- HD Display: Connect to the HDMI port to stream or mirror content to an external monitor in resolutions of up to 4K@30Hz. Note: The USB-C ports do not support video output.
- What You Get: Anker 332 USB-C Hub (5-in-1), welcome guide, our worry-free 18-month warranty, and friendly customer service.
clang main.c -o main
./mainclang++ main.cpp -o main
./mainA compiler is one part of a working toolchain; compiling and linking also depend on the platform’s headers, libraries, linker, and runtime. The Clang users manual describes Clang as one component of a complete toolchain. For a project or course, choose the compiler it supports and check that it supports the required language standard and target platform.
Quick Recap
Fix common compile and run errors
gcc: command not foundorg++: command not found: The compiler is unavailable on your shell’s command search path. Install the appropriate toolchain through your Linux distribution’s package manager; package names and installation commands vary by distribution.- Syntax error or missing header: Read the first compiler diagnostic, verify the source filename, and check that required development headers are installed.
- Undefined references to C++ standard-library symbols: Build or link the C++ program with
g++(orclang++), not the C driver. ./main: No such file or directory: Check that compilation completed successfully, that the-oname matches the file you are trying to run, and that the executable is in the current directory.- Undefined references to your own functions: Make sure the link command includes every required source or object file. If you used
-c, remember that it creates object files but does not link them. - The executable exists but will not run: Read the exact operating-system error. The cause may depend on local permissions, architecture, or runtime libraries; there is no single fix that applies to every Linux system.
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