只从Bash脚本中的路径中获取文件名

许多类unix操作系统都有一个basename可执行文件，用于非常类似的目的(路径为dirname):

pax> full_name=/tmp/file.txt
pax> base_name=$(basename ${full_name})
pax> echo ${base_name}
file.txt

不幸的是，它只给了你文件名，包括扩展名，所以你需要找到一种方法来剥离它。

所以，既然你必须这样做，你也可以找到一个方法，可以剥离路径而且扩展。

一种方法是(这是一个bash-only的解决方案，不需要其他可执行文件):

pax> full_name=/tmp/xx/file.tar.gz
pax> xpath=${full_name%/*}
pax> xbase=${full_name##*/}
pax> xfext=${xbase##*.}
pax> xpref=${xbase%.*}
pax> echo "path='${xpath}', pref='${xpref}', ext='${xfext}'"


path='/tmp/xx', pref='file.tar', ext='gz'

这个小片段设置了xpath(文件路径)，xpref(文件前缀，你具体要求的内容)和xfext(文件扩展名)。

$ source_file_filename_no_ext=${source_file%.*}
$ echo ${source_file_filename_no_ext##*/}

下面是一个从路径中获取文件名的简单方法:

echo "$PATH" | rev | cut -d"/" -f1 | rev

要删除你可以使用的扩展名，假设文件名只有一个点(扩展名点):

cut -d"." -f1

basename和dirname解决方案更方便。这些是可供选择的命令:

FILE_PATH="/opt/datastores/sda2/test.old.img"
echo "$FILE_PATH" | sed "s/.*\///"

它像basename一样返回test.old.img。

这是没有扩展名的salt文件名:

echo "$FILE_PATH" | sed -r "s/.+\/(.+)\..+/\1/"

它返回test.old。

下面的语句给出了完整的路径，如dirname命令。

echo "$FILE_PATH" | sed -r "s/(.+)\/.+/\1/"

它返回/opt/datastores/sda2

还有更多的替代选项，因为正则表达式(regi ?)太棒了!

下面是一个简单的正则表达式来完成这项工作:

 regex="[^/]*$"

例子(grep):

 FP="/hello/world/my/file/path/hello_my_filename.log"
echo $FP | grep -oP "$regex"
#Or using standard input
grep -oP "$regex" <<< $FP

例子(awk):

 echo $FP | awk '{match($1, "$regex",a)}END{print a[0]}
#Or using stardard input
awk '{match($1, "$regex",a)}END{print a[0]} <<< $FP

如果你需要一个更复杂的正则表达式: 例如，你的路径被包装在一个字符串中

 StrFP="my string is awesome file: /hello/world/my/file/path/hello_my_filename.log sweet path bro."


#this regex matches a string not containing / and ends with a period
#then at least one word character
#so its useful if you have an extension


regex="[^/]*\.\w{1,}"


#usage
grep -oP "$regex" <<< $StrFP


#alternatively you can get a little more complicated and use lookarounds
#this regex matches a part of a string that starts with /  that does not contain a /
##then uses the lazy operator ? to match any character at any amount (as little as possible hence the lazy)
##that is followed by a space
##this allows use to match just a file name in a string with a file path if it has an exntension or not
##also if the path doesnt have file it will match the last directory in the file path
##however this will break if the file path has a space in it.


regex="(?<=/)[^/]*?(?=\s)"


#to fix the above problem you can use sed to remove spaces from the file path only
## as a side note unfortunately sed has limited regex capibility and it must be written out in long hand.
NewStrFP=$(echo $StrFP | sed 's:\(/[a-z]*\)\( \)\([a-z]*/\):\1\3:g')
grep -oP "$regex" <<< $NewStrFP

Regexes的整体解决方案:

#you may notice that the sed replace has gotten really crazy looking
#I just added all of the allowed characters in a linux file path
function Get-FileName(){
local FileString="$1"
local NoExtension="$2"
local FileString=$(echo $FileString | sed 's:\(/[a-zA-Z0-9\<\>\|\\\:\)\(\&\;\,\?\*]*\)\( \)\([a-zA-Z0-9\<\>\|\\\:\)\(\&\;\,\?\*]*/\):\1\3:g')


local regex="(?<=/)[^/]*?(?=\s)"


local FileName=$(echo $FileString | grep -oP "$regex")


if [[ "$NoExtension" != "" ]]; then
sed 's:\.[^\.]*$::g' <<< $FileName
else
echo "$FileName"
fi
}


## call the function with extension
Get-FileName "my string is awesome file: /hel lo/world/my/file test/path/hello_my_filename.log sweet path bro."


##call function without extension
Get-FileName "my string is awesome file: /hel lo/world/my/file test/path/hello_my_filename.log sweet path bro." "1"

如果你不得不打乱一个窗口路径，你可以从这个开始:

 [^\\]*$

$ file=${$(basename $file_path)%.*}