如何永久启用从 SCL 存储库安装的较新版本的软件？

Question 1

在您的~/.bashrc或~/.bash_profile简单地获取开发工具集提供的“启用”脚本。例如，使用 Devtoolset 2，命令为：

source /opt/rh/devtoolset-2/enable

或者

source scl_source enable devtoolset-2

效率更高：没有叉子炸弹，没有棘手的外壳

Answer

在您的~/.bashrc或~/.bash_profile简单地获取开发工具集提供的“启用”脚本。例如，使用 Devtoolset 2，命令为：

source /opt/rh/devtoolset-2/enable

或者

source scl_source enable devtoolset-2

效率更高：没有叉子炸弹，没有棘手的外壳

Question 2

的替代方案source /opt/rh/devtoolset-4/enable是

source scl_source enable devtoolset-4

上面的 shell 脚本scl_source比使用硬编码路径更优雅（在另一台机器上可能有所不同）。然而，由于用途和其他东西，scl_source做得较少。/opt/rh/devtoolset-4/enablescl_source

要使用scl_source您可能需要升级包scl-utils

yum update scl-utils  # old scl-utils versions miss scl_source

快速复制粘贴

echo 'source scl_source enable devtoolset-4' >> ~/.bashrc
    # Do not forget to change the version ↑

好奇的人的源代码

源代码示例scl_source：
https://gist.github.com/bkabrda/6435016

安装scl_source在我的 Red Hat 7.1 上

#!/bin/bash

_scl_source_help="Usage: source scl_source <action> [<collection> ...]

Don't use this script outside of SCL scriptlets!

Options:
    -h, --help    display this help and exit"

if [ $# -eq 0 -o $1 = "-h" -o $1 = "--help" ]; then
    echo "$_scl_source_help"
    return 0
fi


if [ -z "$_recursion" ]; then
    _recursion="false"
fi
if [ -z "$_scl_scriptlet_name" ]; then
    # The only allowed action in the case of recursion is the same
    # as was the original
    _scl_scriptlet_name=$1
fi
shift 1

if [ -z "$_scl_dir" ]; then
    # No need to re-define the directory twice
    _scl_dir=/etc/scl/conf
    if [ ! -e $_scl_dir ]; then
        _scl_dir=/etc/scl/prefixes
    fi
fi

for arg in "$@"; do
    _scl_prefix_file=$_scl_dir/$arg
    _scl_prefix=`cat $_scl_prefix_file 2> /dev/null`
    if [ $? -ne 0 ]; then
        echo "Can't read $_scl_prefix_file, $arg is probably not installed."
        return 1
    fi

    # First check if the collection is already in the list
    # of collections to be enabled
    for scl in ${_scls[@]}; do
        if [ $arg == $scl ]; then
            continue 2
        fi
    done

    # Now check if the collection isn't already enabled
    /usr/bin/scl_enabled $arg > /dev/null 2> /dev/null
    if [ $? -ne 0 ]; then
        _scls+=($arg)
        _scl_prefixes+=($_scl_prefix)
    fi;
done

if [ $_recursion == "false" ]; then
    _i=0
    _recursion="true"
    while [ $_i -lt ${#_scls[@]} ]; do
        _scl_scriptlet_path="${_scl_prefixes[$_i]}/${_scls[$_i]}/${_scl_scriptlet_name}"
        source "$_scl_scriptlet_path"
        if [ $? -ne 0 ]; then
            echo "Can't source $_scl_scriptlet_name, skipping."
        else
            export X_SCLS="${_scls[$_i]} $X_SCLS"
        fi;
        _i=$(($_i+1))
    done
    _scls=()
    _scl_prefixes=()
    _scl_scriptlet_name=""
    _recursion="false"
fi

Answer