Building ClamAV® on Mac OS X 10.4 through macOS 15.x Sequoia

Memorandum : Building ClamAV® on Mac OS X 10.4 through macOS 15.x Sequoia

I'm running ClamXav Sentry as 'launch agent' with ClamAV antivirus scanning engine of my own custom build.
I've tested for building ClamAV (from version 0.90.x to version 1.1.x) on Mac OS X 10.4 through macOS 15.x Sequoia.

I'm running the latest stable release ClamAV 1.4.2 on macOS 15.4.1 Sequoia now.
ClamAV 1.4.2 is available on ClamAVNet Download page!
The release notes are here.

As of ClamAV 0.104.x, CMake is required to build ClamAV.
For further information, see the following "Memorandum 0".

Notes: OpenSSL 1.1.1 series will reach End of Life (EOL) on 11th September 2023.
See OpenSSL Blog

This memorandum contains as below:
・ Memorandum    0: Building ClamAV 0.104.x on OS X 10.10 Yosemite through macOS 14.x Sonoma
・ Memorandum    1: Building ClamAV 0.103.x on OS X 10.10 Yosemite through macOS 14.x Sonoma
・ Memorandum    2: Building ClamAV 0.99.x on OS X 10.10, 10.11, 10.12 and macOS 10.13 High Sierra
・ Memorandum    3: Building ClamAV 0.98.7 on OS X 10.10 Yosemite and 10.11 El Capitan
・ Memorandum    4: Building ClamAV on Mac OS X 10.4 (Intel)
・ Memorandum    5: Building ClamAV on Mac OS X 10.4 (PPC)
・ Memorandum    6: Building ClamAV on Mac OS X 10.6 through OS X 10.9 Mavericks
・ Memorandum    7: Running clamd and freshclam as daemon
・ Memorandum    8: Running ClamXav Sentry as 'launch agent' on Mac OS X 10.6 and later…
・ Memorandum    9: Update ClamXav's own Virus Database and running RunFreshclam as daemon
・ Memorandum  10: Running ClamXAV version 2.18.x with B.Y.O. ClamAV antivirus scanning engine
・ Links…

Memorandum 0: Building ClamAV 0.104.x on OS X 10.10 Yosemite through macOS 14.x Sonoma

Building ClamAV 0.104.x on OS X 10.10 Yosemite through macOS 14.x Sonoma

1.  The requirements for building ClamAV 0.104.x or later are completely different from than before.
     Instead of Autotools (eg: ./configure && make && sudo make install), CMake is required to build ClamAV.

2.  For further information, see the following section:
     "How to build ClamAV® with CMake Build System on macOS".

Memorandum 1: Building ClamAV 0.103.x on OS X 10.10 Yosemite through macOS 14.x Sonoma

Building ClamAV 0.103.x on OS X 10.10 Yosemite through macOS 14.x Sonoma

1.  Requirements to build ClamAV 0.103.x is very much the same as building ClamAV 0.102.x.

2.  Requirements to build ClamAV 0.102.x are almost the same as building ClamAV 0.101.x. and ClamAV 0.100.x.

     The differences are as follows:
     LLVM current version is 10.0.x, though ClamAV 1.02.x supports only LLVM =< 3.6.x.
     The ClamAV team is not maintaining repackaged LLVM now, and they may drop the repackaged LLVM entirely
     and deprecate support for system-installed LLVM in favor of the bytecode interpreter.
     So LLVM Libraries are not necessarily required to build ClamAV 0.102.x, I think.

     I am now configuring ClamAV 0.102.x to disable LLVM as follows:

export CPPFLAGS="-I/usr/local/pcre2/include -I/usr/local/libressl/include"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-pcre=/usr/local/pcre2 --with-openssl=/usr/local/libressl \
--enable-llvm=no

Of course you can configure ClamAV 0.102.x to enable LLVM as before:

export CPPFLAGS="-I/usr/local/pcre2/include -I/usr/local/libressl/include"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-pcre=/usr/local/pcre2 --with-openssl=/usr/local/libressl \
--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config \
--with-llvm-linking=static

3. Requirements to build ClamAV 0.102.x and ClamAV 0.101.x are almost same as before.

The following are required as discussed in detail below.

・ PCRE Libraries
・ OpenSSL Libraries
・ LLVM Libraries (Only when enabling LLVM)

4. Differences

The default behavior for clam to link LLVM has been changed dynamically instead of statically.
Thus making ClamAV 0.100.x fails with an error:

ld: library not found for -lLLVM-3.6.2
clang: error: linker command failed with exit code 1 (use -v to see invocation)
make[4]: *** [libclamav.la] Error 1
make[3]: *** [all-recursive] Error 1
make[2]: *** [all] Error 2
make[1]: *** [all-recursive] Error 1
make: *** [all] Error 2

To build ClamAV 0.100.x enabling the LLVM Just-In-Time compiler for executing bytecode signatures,
use this configuration:

./configure --with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config
--with-llvm-linking=static

or simply use this configuration to disable LLVM Just-In-Time compiler:

./configure --enable-llvm=no

Memorandum 2: Building ClamAV 0.99.x on OS X 10.10, 10.11, 10.12 and 10.13 High Sierra

Building ClamAV 0.99.x on OS X 10.10, 10.11, 10.12 and 10.13 High Sierra

ClamAV 0.99.x contains major new features such as YARA rules, PCRE - Perl Compatible Regular Expressions and so on.
To support YARA and ClamAV logical signatures, the Perl Compatible Regular Expressions (PCRE) library is required.
If PCRE isn't installed on your system, you will get a warning message like this while running freshclam.

ClamAV update process started at xxx xxx xx xx:xx:xx xxxx
[LibClamAV] cli_loadldb: logical signature for Win.Trojan.ssidxxxxx uses PCREs but support is
disabled, skipping

1. To ensure the PCRE library:

1) Install PCRE - Perl Compatible Regular Expressions.,

cd ~/Desktop
curl -O https://ftp.pcre.org/pub/pcre/pcre2-10.37.tar.gz
tar zxf pcre2-10.37.tar.gz
cd pcre2-10.37
export CXXFLAGS="-O3"
export CFLAGS="-O3"
./configure --prefix=/usr/local/pcre2
make && make check
sudo make install

2) When compiling ClamAV 0.99.x, it fails with an error:

../libclamav/regex_pcre.h:33:10: fatal error: 'pcre.h' file not found

3) To avoid this failure, simply set CPPFLAGS:

export CPPFLAGS="-I/usr/local/pcre2/include"

4) And add this configuration option when configuring ClamAV: --with-pcre=/usr/local/pcre2.

2. To compile ClamAV 0.99.x on OS X 10.10 Yosemite or on OS X 10.11 El Capitan and macOS 10.12 Sierra,

in addition to the PCRE library;

1) LLVM Library is required on OS X 10.10 Yosemite.
2) LLVM Library and LibreSSL are required on OS X 10.11 El Capitan and macOS 10.12 Sierra.

Please read Memorandum 3 to learn more, and…
3) Install LLVM Library Binaries.
4) Install LibreSSL.

3. Configure ClamAV 0.99.x on OS X 10.10 Yosemite as follws:

export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
export CPPFLAGS="-I/usr/local/pcre2/include"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-pcre=/usr/local/pcre2 \
--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config

4. Configure ClamAV 0.99.x on OS X 10.11 El Capitan and macOS 10.12 Sierra as follws:

export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
export CPPFLAGS="-I/usr/local/pcre2/include -I/usr/local/libressl/include"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-pcre=/usr/local/pcre2 --with-openssl=/usr/local/libressl \
--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config

Memorandum 3: Building ClamAV 0.98.7 on OS X 10.10 Yosemite and 10.11 El Capitan

Building ClamAV 0.98.7 on OS X 10.10 Yosemite

Built-in LLVM of ClamAV 0.98.7 and 0.99.x are not compatible with GNU C++ on OS X 10.10 Yosemite and 10.11 El Capitan.
So ClamAV 0.98.7 and 0.99.x built on OS X 10.10 Yosemite or on OS X 10.11 El Capitan have major issues:

- Clamd crashes repeatedly throwing "Segmentation Fault: 11"
- Clamscan also crashes and fails to scan…
- Freshclam fails to load new database logging:

ERROR: Database load killed by signal 11
ERROR: Failed to load new database: No viruses detected

These problems can be avoided by installing official LLVM.
Versions of LLVM beyond 3.6 seem not to be currently supported in ClamAV, so you should install LLVM 3.6.2.

1. Installing LLVM 3.6.2 Pre-built Binaries

cd ~
curl -O https://releases.llvm.org/3.6.2/clang+llvm-3.6.2-x86_64-apple-darwin.tar.xz

cd /usr/local
sudo tar zxf ~/clang+llvm-3.6.2-x86_64-apple-darwin.tar.xz
sudo chown -R root:wheel /usr/local/clang+llvm-3.6.2-x86_64-apple-darwin

2. To use LLVM installed into /usr/local as a system library instead of the ClamAV's built-in LLVM JIT,
add configuration option as following:

--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config

3. Configure ClamAV 0.98.7 on OS X 10.10.x Yosemite as follws:

export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config

Building ClamAV 0.98.7 on OS X 10.11 El Capitan

Apple introduded a new security feature SIP: System Integrity Protection (rootless) to OS X 10.11 El Capitan, so in /usr directory
OS X 10.11 El Capitan has the different file composition from OS X 10.10 Yosemite.

While configuring ClamAV 0.98.7 on OS X 10.11 El Capitan, configuration fails with an error:

checking for OpenSSL installation... /usr
configure: error: OpenSSL not found.

1. To solve this configuration issue, install LibreSSL.

cd ~/Desktop
curl -LO https://ftp.openbsd.org/pub/OpenBSD/LibreSSL/libressl-3.7.3.tar.gz
tar zxf libressl-3.7.3.tar.gz
cd libressl-3.7.3
export CXXFLAGS="-O3"
export CFLAGS="-O3"
./configure --prefix=/usr/local/libressl
make && make check
sudo make install

Setting search path:

export PATH="/usr/local/libressl/bin:$PATH"

You can confirm the installation:

which openssl
/usr/local/libressl/bin/openssl
openssl version
LibreSSL 3.7.3

2. But it's not still sufficient to succeed building.
Building fails with an error:

bytecode2llvm.cpp:190:10: fatal error: 'openssl/ssl.h' file not found

3. To succeed building ClamAV 0.98.7 on OS X 10.11 El Capitan, set CPPFLAGS:

export CPPFLAGS="-I/usr/local/libressl/include"

4. Configure ClamAV 0.98.7 on OS X 10.11 El Capitan as follws:

export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
export CPPFLAGS="-I/usr/local/libressl/include"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r` \
--with-openssl=/usr/local/libressl \
--with-system-llvm=/usr/local/clang+llvm-3.6.2-x86_64-apple-darwin/bin/llvm-config

5. Notes

Apple has opted to use LibreSSL while providing OpenSSL in OS X 10.11 El Capitan and macOS 10.12 Sierra.
In macOS 10.13 High Sierra, Apple seems to switch SSL libraries from OpenSSL 0.9.8zh to LibreSSL 2.2.7.
LibreSSL is a version of the TLS/crypto stack forked from OpenSSL in 2014.
And it is know to build and work on Mac OS X (tested with 10.8 and later).
So I have changed OpenSSL for LibreSSL to build ClamAV.
Now you can use LibreSSL 2.7.x (the latest stable release).

If you want to use OpenSSL as before, ClamAV 0.100.x is compatible with OpenSSL 1.1.1x,
so you can use OpenSSL 1.1.1x.

cd ~/Desktop
curl -O https://www.openssl.org/source/openssl-1.1.1w.tar.gz
tar zxf openssl-1.1.1w.tar.gz
cd openssl-1.1.1w
./configure darwin64-x86_64-cc --prefix=/usr/local/openssl
make && make test
sudo make install

Setting search path:

export PATH="/usr/local/openssl/bin:$PATH"

Add configure option:

export CPPFLAGS="-I/usr/local/openssl/include"
--with-openssl=/usr/local/openssl

If you use OpenSSL 1.1.1x to compile ClamAV 0.99.x, add more this configuration.

./configure --enable-llvm=no

Memorandum 4 : Building ClamAV on Mac OS X 10.4 (Intel)

Building ClamAV on Mac OS X 10.4 (Intel)

In last update, Clam AntiVirus developer team introduced JIT compiler to ClamAV® 0.96.
Apple gcc (version: 4.0.1 build: 5370) in Mac OS X 10.4 (aka Tiger) failed to build ClamAV 0.96.x and 0.98.x with JIT compiled in.
With a brief struggle I found a good solution that I will tell you here.

1) First, install LLVM (Low Level Virtual Machine) and LLVM-GCC 4.2 Front End.
2) Second, add this configuration option: --enable-llvm.

Then you can build ClamAV 0.96.x and 0.98.x with JIT compiled in and use new features included in anti-virus toolkit.

Install LLVM (Low Level Virtual Machine) and LLVM-GCC 4.2 Front End

1. Installing LLVM-GCC 4.2 Front End Binaries

cd ~
curl -O https://releases.llvm.org/2.3/llvm-gcc4.2-2.3-x86-darwin8.tar.gz
cd /usr/local
sudo tar zxf ~/llvm-gcc4.2-2.3-x86-darwin8.tar.gz

2. Setting search path

export PATH=/usr/local/llvm-gcc4.2-2.3-x86-darwin8/bin:$PATH

3. Installing LLVM 2.3

curl -O http://llvm.org/releases/2.3/llvm-2.3.tar.gz
tar zxf llvm-2.3.tar.gz
cd llvm-2.3
./configure
make
sudo make install

Install MacPorts and the packages

1. Installing MacPorts

Go to their Installing MacPorts page, download the .dmg for your platform, and install it.
Ensure it's up to date by running:

sudo port selfupdate
sudo port sync

2. Installing the packages: bzip2

sudo port install bzip2

3. Maintaining MacPorts and installed packages

sudo port -d selfupdate
sudo port -d sync
sudo port upgrade installed

Compile ClamAV 0.98.x and Install

1. Modify /shared/output.c & output.h to avoid compiling error. (Only needed for compiling ClamAV 0.98.1)

output.c  : off_t logg_size = 0;	->  unsigned int logg_size = 0;
output.h  : extern off_t logg_size;	->  extern unsigned int logg_size;

2. ./configure (version 0.98 and 0.98.1)

cd clamav-0.98.x
export CFLAGS="-O3 -march=i686"
export CXXFLAGS="-O3 -march=i686"
export LDFLAGS="-L/opt/local/lib"
export CC=/usr/local/llvm-gcc4.2-2.3-x86-darwin8/bin/i686-apple-darwin8-gcc-4.2.1
./configure --prefix=/usr/local/clamXav --enable-llvm --build=i686-apple-darwin`uname -r`

3. ./configure (version 0.98.3 or later)

cd clamav-0.98.x
export CFLAGS="-O3 -march=i686"
export CXXFLAGS="-O3 -march=i686"
export LDFLAGS="-L/opt/local/lib"
export CC=/usr/local/llvm-gcc4.2-2.3-x86-darwin8/bin/i686-apple-darwin8-gcc-4.2.1
./configure --with-openssl=/usr/local/ssl --enable-llvm \
--prefix=/usr/local/clamXav --build=i686-apple-darwin`uname -r`

4. Make, make check and install ClamAV

make && make check
sudo make install

To compile ClamAV 0.96.3 or later, bzip2 (Version 1.0.6) that fixes CVE-2010-0405 is required.
Mac OS X has bzip2 (Version 1.0.5) built-in and it is outdated, so you get WARNING as follows while running configuration command.

****** bzip2 libraries are affected by the CVE-2010-0405 bug
****** We strongly suggest you to update bzip2


****** WARNING:
****** You are cross compiling to a different host or you are
****** linking to bugged system libraries or you have manually
****** disabled important configure checks.
****** Please be aware that this build may be badly broken.
****** DO NOT REPORT BUGS BASED ON THIS BUILD !!!

To solve this problem on Mac OS X 10.4, you can install bzip2 (Version 1.0.6) using MacPorts and add this configuration option:
export LDFLAGS="-L/opt/local/lib" as follows.

Apple has patched the CVE-2010-0405 bug on Mac OS X 10.6.7 but not on Mac OS X 10.4.11.

To compile ClamAV 0.98.3 or later, OpenSSL (Version 0.98y or above including the X509_VERIFY_PARAM function) is required.
Mac OS X 10.4 has OpenSSL 0.9.7l built-in and MacPorts fails to build OpenSSL, so you have to install OpenSSL 0.9.8zh.

1. Install OpenSSL 0.9.8zh

cd ~/Desktop
curl -O https://www.openssl.org/source/openssl-0.9.8zh.tar.gz
tar zxf openssl-0.9.8zh.tar.gz
cd openssl-0.9.8zh
./Configure darwin-i386-cc --prefix=/usr/local/ssl
make
sudo make install

2. Setting search path

export PATH="/usr/local/ssl/bin:$PATH"

Compile ClamAV 0.99.x and Install

To compile ClamAV 0.99.x on Mac OS X 10.4, in addition to installing LLVM Front End, MacPorts, bzip2 and OpenSSL the PCRE library is required as pointed out above.

1. Install PCRE - Perl Compatible Regular Expressions.

cd ~/Desktop
curl -O ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-8.40.tar.gz
tar zxf pcre-8.40.tar.gz
cd pcre-8.40
./configure --prefix=/usr/local/pcre
make && make check
sudo make install

2. ./configure

cd clamav-0.99.x
export CFLAGS="-O3 -march=i686"
export CXXFLAGS="-O3 -march=i686"
export LDFLAGS="-L/opt/local/lib"
export CC=/usr/local/llvm-gcc4.2-2.3-x86-darwin8/bin/i686-apple-darwin8-gcc-4.2.1
./configure --with-openssl=/usr/local/ssl --with-pcre=/usr/local/pcre  --enable-llvm \
--prefix=/usr/local/clamXav --build=i686-apple-darwin`uname -r`

3. Make, make check and install ClamAV

make && make check
sudo make install

Memorandum 5 : Building ClamAV on Mac OS X 10.4 (PPC)

Building ClamAV on Mac OS X 10.4 (PPC)

PPC users have to install LLVM-GCC 4.2 Front End Binaries for PPC and configure ClamAV 0.96.x and 0.98.x with different configuration.

Install LLVM (Low Level Virtual Machine) and LLVM-GCC 4.2 Front End

1. Installing LLVM-GCC 4.2 Front End Binaries

cd ~
curl -O https://releases.llvm.org/2.3/llvm-gcc4.2-2.3-ppc-darwin8.11.0.tar.gz
cd /usr/local
sudo tar zxf ~/llvm-gcc4.2-2.3-ppc-darwin8.11.0.tar.gz

2. Setting search path

export PATH=/usr/local/llvm-gcc4.2-2.3-ppc-darwin8.11.0/bin:$PATH

3. Installing LLVM 2.3

curl -O http://llvm.org/releases/2.3/llvm-2.3.tar.gz
tar zxf llvm-2.3.tar.gz
cd llvm-2.3
./configure
make
sudo make install

Install MacPorts and the packages

1. Installing MacPorts

Go to their Installing MacPorts page, download the .dmg for your platform, and install it.
Ensure it's up to date by running:

sudo port selfupdate
sudo port sync

2. Installing the packages: bzip2

sudo port install bzip2

3. Maintaining MacPorts and installed packages

sudo port -d selfupdate
sudo port -d sync
sudo port upgrade installed

Compile ClamAV 0.98.x and Install

1. Modify /shared/output.c & output.h to avoid compiling error. (Only needed for compiling ClamAV 0.98.x)

output.c  : off_t logg_size = 0;	->  unsigned int logg_size = 0;
output.h  : extern off_t logg_size;	->  extern unsigned int logg_size;

2. ./configure

cd clamav-0.98.x
export CFLAGS="-O3"
export CXXFLAGS="-O3"
export LDFLAGS="-L/opt/local/lib"
export CC=/usr/local/llvm-gcc4.2-2.3-ppc-darwin8.11.0/bin/powerpc-apple-darwin8-gcc-4.2.1
./configure --prefix=/usr/local/clamXav --enable-llvm

3. Make, make check and install ClamAV

make && make check
sudo make install

Memorandum 6 : Building ClamAV on Mac OS X 10.6 through OS X 10.9 Mavericks

Building ClamAV on Mac OS X 10.6 through OS X 10.9

GNU C++ and bzip2 (Version 1.0.6) are installed on Mac OS X and later, so you can simply build ClamAV 0.96.x and 0.98.x with JIT compiled in and use new features included in anti-virus toolkit.

1. On Mac OS X 10.7, after installing Xcode 4.3 in /Applications, you should install the Command Line Tools:

from "Xcode -> Preferences -> Downloads -> Components pane", or install them via the separate installer from
developer.apple.com. and

2. Run these commands to make sure that everything is pointed in the right place.

sudo xcode-select -switch /Applications/Xcode.app

Compile ClamAV 0.98.x and Install

1. ./configure

cd clamav-0.98.x
export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
./configure --prefix=/usr/local/clamXav --build=x86_64-apple-darwin`uname -r`
--enable-llvm

2. Make, make check and install ClamAV

make && make check
sudo make install

Compile ClamAV 0.99.x and Install

1. To compile ClamAV 0.99.x, the PCRE library is required as pointed out above.

Install PCRE - Perl Compatible Regular Expressions.

cd ~/Desktop
curl -O ftp://ftp.csx.cam.ac.uk/pub/software/programming/pcre/pcre-8.40.tar.gz
tar zxf pcre-8.40.tar.gz
cd pcre-8.40
./configure --prefix=/usr/local/pcre
make && make check
sudo make install

2. ./configure

cd clamav-0.99.x
export CFLAGS="-O3 -march=nocona"
export CXXFLAGS="-O3 -march=nocona"
./configure --prefix=/usr/local/clamXav --with-pcre=/usr/local/pcre --enable-llvm \
--build=x86_64-apple-darwin`uname -r`

3. Make, make check and install ClamAV

make && make check
sudo make install

Memorandum 7: Running clamd and freshclam as 'launch daemon'

Running clamd and freshclam as 'launch daemon'

1. I'm running clamd and freshclam as 'launch daemon' managed by:

/Library/LaunchDaemons/org.clamav.clamd.plist
/Library/LaunchDaemons/org.clamav.freshclam.plist

sudo chown root:wheel /Library/LaunchDaemons/org.clamav.clamd.plist
sudo chmod 0644 /Library/LaunchDaemons/org.clamav.clamd.plist
sudo chown root:wheel /Library/LaunchDaemons/org.clamav.freshclam.plist
sudo chmod 0644 /Library/LaunchDaemons/org.clamav.freshclam.plist

2. Edit clamd.conf and freshclam.conf for using ' daemons'.

3. Set appropriate permissions for ClamXav and ClamXav Sentry.

sudo bash
chown -R root:admin /usr/local/clamXav
chown -R root:admin /usr/local/clamXav/etc
chmod 0775 /usr/local/clamXav/etc
chmod 0644 /usr/local/clamXav/etc/*
chown -R root:admin /usr/local/clamXav/bin
chmod 0755 /usr/local/clamXav/bin
chmod 0755 /usr/local/clamXav/bin/*
chown -R clamav:clamav /usr/local/clamXav/share/clamav
chmod -R g+w /usr/local/clamXav/share/clamav
chmod -R u+w /usr/local/clamXav/share/clamav
chmod 0755 /usr/local/clamXav/share/clamav
chmod 0644 /usr/local/clamXav/share/clamav/*
chmod 0644 /usr/local/clamXav/share/clamav/freshclam.log
chown clamav:admin /var/log/clamd.log
chmod 0664 /var/log/clamd.log

4. Notes

When using 'daemon' to launch freshclam,
uncheck "Update virus definitions on launch" of ClamXav's 'General Preferences' section.
Updates of virus definitions gets executed automatically by 'freshclam daemon'.

Memorandum 8: Running ClamXav Sentry as 'launch agent' on Mac OS X 10.6 and later…

Running ClamXav Sentry as 'launch agent' on Mac OS X 10.6 and later…

1. When running ClamXav Sentry as 'launch agent', ClamXav Sentry keeps alive.

So even if it crashes, it gets back and keeps watching files and folders without any incident.
I'm running ClamXav Sentry as 'launch agent' managed by ~/Library/LaunchAgents/org.clamXavSentry.plist

2. On Yosemite and El Capitan, I'm using this org.clamXavSentry.plist file to avoid ClamXav Sentry's annoying error:

ERROR: Can't connect to clamd: No such file or directory
Total errors: 1
connect(): No such file or directory
ClamXavSentry can't connect to clamd
Error, can't connect to clamd through /tmp/clamd.socket.

3. Notes

When using 'launch agent' to launch ClamXav Sentry,
uncheck "Launch ClamXav Sentry when you log in to this computer" of 'ClamXav Sentry Preferences' section.
ClamXav Sentry automatically launches and keeps alive by 'launch agent' when logging in.

CFBundleExecutable name "ClamXavSentry" was replaced by "ClamXav Sentry" in ClamXav 2.7.x.
So you should replace "ClamXavSentry" with "ClamXav Sentry" in org.clamXavSentry.plist.

If you are running clamd as 'launch daemon' and running ClamXav Sentry 3.x as 'launch agent',
use this hidden preference setting:

defaults write uk.co.markallan.clamxav clamdControlledExternally -bool YES;
killall cfprefsd

And if you are running clamd as 'launch daemon' and running ClamXav Sentry 3.5.x as 'launch agent',
use this hidden preference setting:

defaults write uk.co.canimaansoftware.clamxav clamdControlledExternally -bool YES;
killall cfprefsd

Memorandum 9 : Update ClamXav's own Virus Database and running RunFreshclam as daemon

Update ClamXav's own Virus Database

1. Now ClamXav and ClamXav Sentry use combined official and its own virus database as below:

Database information
--------------------
Database directory: /usr/local/clamXav/share/clamav
bytecode.cld: version 283, sigs: 53, built on Fri Jun 24 00:01:37 2016
[3rd Party] ClamXav.fp: 19 sigs
[3rd Party] ClamXav.hdb: 78676 sigs
[3rd Party] ClamXav.ndb: 7 sigs
daily.cld: version 21786, sigs: 342508, built on Sat Jun 25 15:15:10 2016
main.cvd: version 57, sigs: 4218790, built on Thu Mar 17 08:17:06 2016
Total number of signatures: 4640053

2. To get and update ClamXav Virus Database,

extract RunFreshclam from the latest ClamXav.app/Contents/Resources/clamavEngineInstaller.pkg
and place it into

/usr/local/clamXav/bin

ClamXav 2.8.9.4 requires empty file called 0.99.1_update_4 inside /usr/local/clamXav.

sudo touch /usr/local/clamXav/0.99.1_update_4

3. When you launch ClamXav 2.8.9.1 and update virus definitions, ClamXav logs follwing error:

ClamXav[*****]: /usr/local/clamXav/bin/freshclam: unrecognized option `--show-progress'
ERROR: Unknown option passed
ERROR: Can't parse command line options

ClamXav 2.8.9.1 requires freshclam compiled with option '--show-progress'.
For details, see "Bug 11455 – [Clamav-devel] Patch to force freshclam download progress meter".
To solve this issue, get and apply 'freshclam_show-progress.patch' before you build ClamAV 0.99.0.
--------
The patch has been checked in ClamAV 0.99.1 repository, so no need for patching to build ClamAV 0.99.1.

Running RunFreshclam as 'daemon' instead of freshclam daemon

1. I'm now running RunFreshclam as 'daemon' instead of freshclam daemon managed by:
/Library/LaunchDaemons/com.clamXav.runfreshclam.plist

sudo chown root:wheel /Library/LaunchDaemons/com.clamXav.runfreshclam.plist
sudo chmod 0644 /Library/LaunchDaemons/com.clamXav.runfreshclam.plist

2. Edit freshclam.conf for using RunFreshclam ' daemons'.

3. Set appropriate permissions for RunFreshclam (ClamXav version =< 2.8.x).

sudo bash
chown -R root:wheel /usr/local/clamXav
chmod 0775 /usr/local/clamXav/etc
chmod 0664 /usr/local/clamXav/etc/*
chmod 0644 /usr/local/clamXav/etc/freshclam.conf
chmod 0755 /usr/local/clamXav/bin
chmod 0755 /usr/local/clamXav/bin/*
chmod u+s /usr/local/clamXav/bin/freshclam
chmod u+s /usr/local/clamXav/bin/RunFreshclam
chown -R clamav:clamav /usr/local/clamXav/share/clamav
chmod 0775 /usr/local/clamXav/share/clamav
chmod 0644 /usr/local/clamXav/share/clamav/*
chmod 0666 /usr/local/clamXav/share/clamav/freshclam.log

Notes:
As concerns appropriate permissions on ClamXav 2.9.x, see described below.

4. Checking and updating virus definitions:

When running 'RunFreshclam' as ' daemon',
'RunFreshclam' automatically (at regular time intervals, e.g. every 30minutes or every 1 hour as you set) executes checking and updating both ClamXav's own virus definitions and official ClamAV® virus definitions, so you need not run 'freshclam daemon'.

An example of freshclam.log:

----------------------------------------------------------------------------
Checking Official ClamXav definitions
--------------------------------------
Update process started at Jun 24, 2016, 5:06:05 PM
ClamXav.ndb is already up to date.
ClamXav.hdb is valid and has file size: 4691872 bytes
DB integrity check is sound. Move ClamXav.hdb into place
ClamXav.fp is already up to date.
ClamXav.ign2 is already up to date.
ClamXav.plist is already up to date.
Nothing to download for ClamXav.ldb

Checking ClamAV definitions
--------------------------------------
ClamAV update process started at Fri Jun 24 17:06:15 2016
main.cvd is up to date (version: 57, sigs: 4218790, f-level: 60, builder: amishhammer)
Downloading daily-21776.cdiff [100%]
Downloading daily-21777.cdiff [100%]
Downloading daily-21778.cdiff [100%]
Downloading daily-21779.cdiff [100%]
Downloading daily-21780.cdiff [100%]
daily.cld updated (version: 21780, sigs: 337592, f-level: 63, builder: neo)
Downloading bytecode-282.cdiff [100%]
Downloading bytecode-283.cdiff [100%]
bytecode.cld updated (version: 283, sigs: 53, f-level: 63, builder: neo)
Database updated (4556435 signatures) from cdn.clamxav.com (IP: 43.249.37.245)
Clamd successfully notified about the update.
----------------------------------------------------------------------------

Memorandum 10 : Running ClamXAV version 2.19.x with B.Y.O. ClamAV engine

To run ClamXAV 2.19.x and ClamXAV Sentry 3.19.x with B.Y.O.E.

1. ClamXav has a new engine install and uninstall mechanism since version 2.9.

Now ClamXav examines whether all the files necessary for ClamXav are installed exactly, and investigates whether the permissions on all files and folders at /usr/local/clamXav are right.
When you fail to satisfy the requirements, ClamXav tries to repair /usr/local/clamXav, and all files and folders are changed to its own official engine.

To satisfy the requirements, the following files are needed at the very least in addition to B.Y.O. ClamAV files:

/usr/local/clamXav/0.xx.x_update_x
/usr/local/clamXav/bin/gfslogger
/usr/local/clamXav/bin/RunFreshclam

2. Steps to satisfy the requirements for ClamXAV Version 2.19.4 (3723):

1) make empty file called 0.100.1_update_09 inside /usr/local/clamXav/

sudo touch /usr/local/clamXav/0.100.1_update_09

2) extract gfslogger and RunFreshclam from ClamXAV.app/Contents/Resources/clamavEngineInstaller.pkg

3) place those files into appropriate directory:

/usr/local/clamXav/bin/

4) ClamXav 2.11.x changed the name of two files located at /usr/local/clamXav/share/clamav/.
First run RunFreshclam completely, then you can place them at /usr/local/clamXav/share/clamav/ as follws:

/usr/local/clamXav/share/clamav/ClamXav.database
/usr/local/clamXav/share/clamav/ClamXav.database.signature

An example of files located at /usr/local/clamXav/share/clamav:

ls -l /usr/local/clamXav/share/clamav
total 1037960
-rw-rw-r--  1 _clamav  _clamav      31275 Jun 18 17:39 ClamXav.blacklist
-rw-rw-r--  1 _clamav  _clamav      81744 Jun 15 06:30 ClamXav.database
-rw-rw-r--  1 _clamav  _clamav         65 Jun 15 06:30 ClamXav.database.signature
-rw-rw-r--  1 _clamav  _clamav       2470 Jun 15 06:30 ClamXav.fp
-rw-rw-r--  1 _clamav  _clamav   68197258 Jun 19 18:21 ClamXav.hdb
-rw-rw-r--  1 _clamav  _clamav        963 Jun 19 23:47 ClamXav.ign2
-rw-rw-r--  1 _clamav  _clamav      10594 Jun 15 06:30 ClamXav.ldb
-rw-rw-r--  1 _clamav  _clamav       6249 Jun 15 06:30 ClamXav.ndb
-rw-rw-r--  1 _clamav  _clamav     972288 Jun 20 08:27 bytecode.cld
-rw-rw-r--  1 _clamav  _clamav  142264832 Jun 20 08:27 daily.cld
-rw-rw-rw-  1 _clamav  _clamav      25909 Jun 20 08:27 freshclam.log
-rw-rw-r--  1 _clamav  _clamav  307499008 Jun 15 06:30 main.cld

5) Set appropriate permissions at /usr/local/clamXav for ClamXAV 2.19.x.

sudo bash
chown -R root:wheel /usr/local/clamXav
chmod 0775 /usr/local/clamXav/etc
chmod 0664 /usr/local/clamXav/etc/*
chown clamav:wheel /usr/local/clamXav/etc/freshclam.conf
chmod 0600 /usr/local/clamXav/etc/freshclam.conf
chmod 0755 /usr/local/clamXav/bin
chmod 0755 /usr/local/clamXav/bin/*
chown clamav:wheel /usr/local/clamXav/bin/freshclam
chmod u+s /usr/local/clamXav/bin/freshclam
chmod u+s /usr/local/clamXav/bin/gfslogger
chmod g+s /usr/local/clamXav/bin/gfslogger
chmod u+s /usr/local/clamXav/bin/RunFreshclam
chown -R clamav:clamav /usr/local/clamXav/share/clamav
chmod 0775 /usr/local/clamXav/share/clamav
chmod 0664 /usr/local/clamXav/share/clamav/*
chmod 0666 /usr/local/clamXav/share/clamav/freshclam.log

3. Now you can run ClamXAV Sentry 3.19.x as 'launch agent' and run RunFreshclam as 'launch daemon' with no issues.

As a matter of course you can launch ClamXAV 2.19.x and it works all right.

An example of freshclam.log:

----------------------------------------------------------------------------
Checking Official ClamXAV definitions
--------------------------------------
Update process started at Jun 20, 2018 at 8:26:24 AM
ClamXav.ndb is already up to date.
ClamXav.hdb.zip is valid and has file size: 26280007 bytes
DB integrity check is sound. Move ClamXav.hdb into place
ClamXav.fp is already up to date.
ClamXav.ign2 is valid and has file size: 963 bytes
DB integrity check is sound. Move ClamXav.ign2 into place
ClamXav.database is already up to date.
ClamXav.ldb is already up to date.

Checking ClamAV definitions
--------------------------------------
ClamAV update process started at Wed Jun 20 08:27:29 2018
main.cld is up to date (version: 58, sigs: 4566249, f-level: 60, builder: sigmgr)
Downloading daily-24677.cdiff [100%]
Downloading daily-24678.cdiff [100%]
daily.cld updated (version: 24678, sigs: 1987884, f-level: 63, builder: neo)
Downloading bytecode-320.cdiff [100%]
bytecode.cld updated (version: 320, sigs: 93, f-level: 63, builder: neo)
Database updated (6554226 signatures) from db.jp.clamav.net (IP: 104.16.187.138)
Clamd successfully notified about the update.
----------------------------------------------------------------------------

4. Important Notes

Canimaan Software Ltd released ClamXav Version 2.9 (2378) and then has stopped official support for B.Y.O. Engine.
If you keep using B.Y.O. Engine, do that on your own risk.

Now ClamXAV 3 is available, thus ClamXAV 2 will not receive malware database updates beyond 31st October 2018.

I have not verified ClamXAV 3 because I don't use ClamXAV 3 now.

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