由于linux编译出的so经常会在后面带有版本号，而程序加载的是不带版本号的so，导致经常出现so找不的情况，这个时候为带版本号的so创建一个符号链接（软链接）就好了。
在终端输入ln --help查看一下这个命令的用法如下：
用法：ln [选项]... [-T] 目标 链接名 (第一种格式)
或：ln [选项]... 目标 (第二种格式)
或：ln [选项]... 目标... 目录 (第三种格式)
或：ln [选项]... -t 目录 目标... (第四种格式)
In the 1st form, create a link to TARGET with the name LINK_NAME.
In the 2nd form, create a link to TARGET in the current directory.
In the 3rd and 4th forms, create links to each TARGET in DIRECTORY.
Create hard links by default, symbolic links with --symbolic.
By default, each destination (name of new link) should not already exist.
When creating hard links, each TARGET must exist. Symbolic links
can hold arbitrary text; if later resolved, a relative link is
interpreted in relation to its parent directory.
必选参数对长短选项同时适用。
--backup[=CONTROL] 为每个已存在的目标文件创建备份文件
-b 类似--backup，但不接受任何参数
-d, -F, --directory 创建指向目录的硬链接(只适用于超级用户)
-f, --force 强行删除任何已存在的目标文件
-i, --interactive prompt whether to remove destinations
-L, --logical dereference TARGETs that are symbolic links
-n, --no-dereference treat LINK_NAME as a normal file if
it is a symbolic link to a directory
-P, --physical make hard links directly to symbolic links
-r, --relative create symbolic links relative to link location
-s, --symbolic make symbolic links instead of hard links
-S, --suffix=SUFFIX override the usual backup suffix
-t, --target-directory=DIRECTORY specify the DIRECTORY in which to create
the links
-T, --no-target-directory treat LINK_NAME as a normal file always
-v, --verbose print name of each linked file
--help 显示此帮助信息并退出
--version 显示版本信息并退出
The backup suffix is '~', unless set with --suffix or SIMPLE_BACKUP_SUFFIX.
The version control method may be selected via the --backup option or through
the VERSION_CONTROL environment variable. Here are the values:
none, off 不进行备份(即使使用了--backup 选项)
numbered, t 备份文件加上数字进行排序
existing, nil 若有数字的备份文件已经存在则使用数字，否则使用普通方式备份
simple, never 永远使用普通方式备份
Using -s ignores -L and -P. Otherwise, the last option specified controls
behavior when a TARGET is a symbolic link, defaulting to -P.
GNU coreutils online help:
请向 报告ln 的翻译错误
Full documentation at:
or available locally via: info '(coreutils) ln invocation'
