How can I link the 3rd party library bzip2 in my gcc compiler?

问题

I'm a python developer new to C and developing C code on Windows that needs to work on Windows and Linux.

To that end, I downloaded MSYS2 and used pacman to install gcc and bz2.

My question is: How do I use bzip2 in my C code.

When I try to compile this C code:

#include <bzlib.h>

using the command gcc test.c -lbzip2 -o test.out I get the following error:

test.c:1:10: fatal error: bzlib.h: No such file or directory

Am I including the correct header file? Am I linking it correctly?

When not using 3rd party libraries a simple "hello world" program compiles and executes fine.

回答1:

Short version: assuming you are using the MSYS target, pacman -S libbz2-devel.

---

Long version: In MSYS2 you can find which package contains a file using:

pacman -F bzlib.h

to which the answer is:

mingw32/mingw-w64-i686-bzip2 1.0.8-1 [installed]
    mingw32/include/bzlib.h
mingw64/mingw-w64-x86_64-bzip2 1.0.8-1 [installed]
    mingw64/include/bzlib.h
msys/libbz2-devel 1.0.8-1 (development)
    usr/include/bzlib.h

To interpret this output, first understand that an MSYS2 installation supports three different development targets:

• mingw32 (builds native Win32 applications using mingw-w64)
• mingw64 (builds native Win64 applications using mingw-w64)
• msys (builds Win32 or Win64 applications that depend on MSYS DLLs and runtime environment, using a custom GCC port and runtime library, and supports a lot of POSIX functionality).

When you install MSYS2 you will get three startup scripts in the Start Menu , one for each of those environments.

The output of pacman -F above told us that for targets mingw32 and mingw64, the package bzip2 contains the files required to do development with bzip. However, on the msys target, the package libbz2-devel is required.

This is a common package layout in msys and in the various *nix package managers (MSYS2 pacman is a port of ArchLinux pacman):

• bzip2 is the binaries for using bzip2 in your shell
• libbz2 is a shared object binary (DLL)
• libbz2-devel is the header files and static libraries that you need to link bzip2 into your program.

You can list the files for each package with pacman -F --list libbz2-devel etc.

The mingw32/mingw64 targets typically have single packages that include all of those three things in the one package, e.g. pacman -F --list mingw64/mingw-w64-x86_64-bzip2.

I assume you are using msys target as otherwise this question would not have arisen .

回答2:

Installing all the binary packages listed here and changing the header filename to bzlib.h fixed the problem.

来源：https://stackoverflow.com/questions/62224480/how-can-i-link-the-3rd-party-library-bzip2-in-my-gcc-compiler