fixes from review

README.rst

@@ -42,7 +42,7 @@ The Travis CI scripts are designed to build *and test*:
 * 64-bit macOS wheels built for macOS 10.9+
 * 64/32-bit macOS wheels built for macOS 10.6+
 * 64-bit ``manylinuxX_x86_64`` wheels, both narrow and wide Unicode builds,
-  where `X` is any valid Manylinux version, such as `1`, or `2010`
+  where `X` is any valid Manylinux version: `1`, `2010`, `2014` or `_2_24`.
 * 32-bit ``manylinuxX_i686`` wheels, both narrow and wide Unicode builds
 
 You can currently build and test against Pythons 2.7, 3.5, 3.6, 3.7, 3.8 and 3.9

common_utils.sh

@@ -27,7 +27,8 @@ UNICODE_WIDTH=${UNICODE_WIDTH:-32}
 if [ $(uname) == "Darwin" ]; then
   IS_MACOS=1; IS_OSX=1;
 else
-  # In the manylinux_2_24 image, based on Debian9, python2 is not installed
+  # In the manylinux_2_24 image, based on Debian9, "python" is not installed
+  # so link in something for the various system calls before PYTHON_EXE is set
   which python || export PATH=/opt/python/cp39-cp39/bin:$PATH
 fi
 
@@ -205,12 +206,15 @@ function untar {
 }
 
 function install_rsync {
+    # install rsync via package manager
     if [ -n "$IS_MACOS" ]; then
         # macOS. The colon in the next line is the null command
         :
     elif [[ $MB_ML_VER == "_2_24" ]]; then
+        # debian:9 based distro
         [[ $(type -P rsync) ]] || apt-get install -y rsync
     else
+        # centos based distro
         [[ $(type -P rsync) ]] || yum_install rsync
     fi
 }

configure_build.sh

@@ -47,24 +47,19 @@ else
     export CFLAGS="${CFLAGS:-$STRIP_FLAGS}"
     export CXXFLAGS="${CXXFLAGS:-$STRIP_FLAGS}"
     export FFLAGS="${FFLAGS:-$STRIP_FLAGS}"
-    if [[ $MB_ML_VER == "1" ]]; then
-        if [ "${MB_PYTHON_VERSION:0:4}" == "pypy" ]; then
-            yum install -y libtool wget
-        else
-            yum install -y libtool
-        fi
-    elif [[ $MB_ML_VER == "_2_24" ]]; then
+    if [[ $MB_ML_VER == "_2_24" ]]; then
+        # This is the first opportunity to distinguish between manylinux's
         apt update
-        if [ ! -d /usr/local/man ]; then
-            # Fix problem with manylinux_2_24 image
-            # /usr/local/man is a broken symlink
-            rm /usr/local/man
-            ln -s /usr/share/man /usr/local/man
-        fi
         if [ "${MB_PYTHON_VERSION:0:4}" == "pypy" ]; then
+            # debian:9 based distro
             apt install -y wget
         fi
+    elif [[ $MB_ML_VER == "1" ]]; then
+        # Need libtool, and for pypy need wget
+        # centos based distro
+        yum install -y libtool wget
     elif [ "${MB_PYTHON_VERSION:0:4}" == "pypy" ]; then
+        # centos based distro
         yum install -y wget
     fi
 fi

library_builders.sh

@@ -134,8 +134,10 @@ function build_zlib {
     if [ -n "$IS_MACOS" ]; then return; fi  # OSX has zlib already
     if [ -e zlib-stamp ]; then return; fi
     if [[ $MB_ML_VER == "_2_24" ]]; then
+        # debian:9 based distro
         apt-get install -y zlib1g-dev
     else
+        #centos based distro
         yum_install zlib-devel
     fi
     touch zlib-stamp
@@ -185,11 +187,13 @@ function get_modern_cmake {
     if [ -n "$IS_MACOS" ]; then
         brew install cmake > /dev/null
     elif [[ $MB_ML_VER == "_2_24" ]]; then
+        # debian:9 based distro
         apt-get install -y cmake
     else
         if [ "`yum search cmake | grep ^cmake28\.`" ]; then
             cmake=cmake28
         fi
+        # centos based distro
         yum_install $cmake > /dev/null
     fi
     echo $cmake
@@ -403,8 +407,10 @@ function build_suitesparse {
     if [ -n "$IS_MACOS" ]; then
         brew install suite-sparse > /dev/null
     elif [[ $MB_ML_VER == "_2_24" ]]; then
+        # debian:9 based distro
         apt-get install -y libsuitesparse-dev > /dev/null
     else
+        # centos based distro
         yum_install suitesparse-devel > /dev/null
     fi
     touch suitesparse-stamp

manylinux_utils.sh

@@ -45,8 +45,10 @@ function activate_ccache {
 
     # Now install ccache
     if [[ $MB_ML_VER == "_2_24" ]]; then
+        # debian:9 based distro
         suppress apt-get install -y ccache
     else
+        # centos based distro
         suppress yum_install ccache
     fi