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在bash中,文件运算符(-f)是否可以不区分大小写?

case-insensitive bash

Paul Richter · 技术社区 · 14 年前

我正在做以下工作:

if [ -f $FILE ] ; then
    echo "File exists"
fi

但是我想要 -f 不区分大小写。也就是说,如果文件 /etc/somefile ,我要-f来识别 /Etc/SomeFile

我可以用glob部分解决这个问题:

shopt -s nocaseglob
TARG='/etc/somefile'

MATCH=$TARG*    #assume it returns only one match

if [[ -f $MATCH ]] ; then
    echo "File exists" 
fi

但是不区分大小写的globbing只对文件名部分有效,而不是对完整路径有效。所以如果TARG是 /Etc/somefile

有什么办法吗?

6 回复 | 直到 12 年前

Pablo Bianchi 5 年前

文件系统

考虑到所有这些,这是可行的:

if [[ -n $(find /etc -maxdepth 1 -iname passwd) ]]; then
  echo "Found";
fi

但是,除非要搜索从“/”开始的所有内容,否则必须逐个检查路径的组件。这是没有办法的;在一个区分大小写的文件系统上,你不能神奇地检查整个路径是否有不区分大小写的匹配!

Jokester 14 年前

不知道如何只使用shell计算。但是grep可以不区分大小写,因此调用grep、find和wc的脚本可以满足您的需求。

ghostdog74 14 年前

您可以使用nocasematch选项

shopt -s nocasematch
for file in *
do
  case "$file" in
   "/etc/passWd" ) echo $file;;
  esac
done

Philipp 14 年前

import os

def exists_nocase(path):
    if os.path.exists(path):
        return True
    path = os.path.normpath(os.path.realpath(os.path.abspath(unicode(path)))).upper()
    parts = path.split(os.sep)
    path = unicode(os.path.join(unicode(os.path.splitdrive(path)[0]), os.sep))
    for name in parts:
        if not name:
            continue
        # this is a naive and insane way to do case-insensitive string comparisons:
        entries = dict((entry.upper(), entry) for entry in os.listdir(path))
        if name in entries:
            path = os.path.join(path, entries[name])
        else:
            return False
    return True

print exists_nocase("/ETC/ANYTHING")
print exists_nocase("/ETC/PASSWD")

carlo 14 年前

cd /etc
# using FreeBSD find
find -x -L "$(pwd)" -maxdepth 1 -type f -iregex "/EtC/[^\/]*" -iname paSSwd

juan 14 年前

#  fci -- check if file_case_insensitive exists 
# (on a case sensitive file system; complete file paths only!)

function fci() {   

declare IFS checkdirs countslashes dirpath dirs dirstmp filepath fulldirpaths i name ndirs result resulttmp

[[ -f "$1" ]] && { return 0; }
[[ "${1:0:1}" != '/' ]] && { echo "No absolute file path given: ${1}" 2>&1; return 1; }
[[ "$1" == '/' ]] && { return 1; }

filepath="$1"
filepath="${filepath%"${filepath##*[!/]}"}"  # remove trailing slashes, if any
dirpath="${filepath%/*}"
name="${filepath##*/}"

IFS='/'
dirs=( ${dirpath} )

if [[ ${#dirs[@]} -eq 0 ]]; then
   fulldirpaths=( '/' )
   ndirs=1
else
   IFS=""
   dirs=( ${dirs[@]} )
   ndirs=${#dirs[@]}

   for ((i=0; i < ${ndirs}; i++)); do

      if [[ $i -eq 0 ]]; then
         checkdirs=( '/' )
      else
         checkdirs=( "${dirstmp[@]}" )
      fi

      IFS=$'\777'
      dirstmp=( $( find -x -L "${checkdirs[@]}" -mindepth 1 -maxdepth 1 -type d -iname "${dirs[i]}" -print0 2>/dev/null | tr '\0' '\777' ) )

      IFS=""
      fulldirpaths=( ${fulldirpaths[@]} ${dirstmp[@]} )

   done

fi

printf "fulldirpaths: %s\n" "${fulldirpaths[@]}" | nl

for ((i=0; i < ${#fulldirpaths[@]}; i++)); do
   countslashes="${fulldirpaths[i]//[^\/]/}"
   [[ ${#countslashes} -ne ${ndirs} ]] && continue
   IFS=$'\777'
   resulttmp=( $( find -x -L "${fulldirpaths[i]}" -mindepth 1 -maxdepth 1 -type f -iname "${name}" -print0 2>/dev/null | tr '\0' '\777' ) )
   IFS=""
   result=( ${result[@]} ${resulttmp[@]} )
done

IFS=""
result=( ${result[@]} )

printf "result: %s\n" "${result[@]}" | nl

if [[ ${#result[@]} -eq 0 ]]; then
   return 1
else
   return 0
fi
}


FILE='/eTC/paSSwD'

if fci "${FILE}" ; then
   echo "File (case insensitive) exists: ${FILE}" 
else
   echo "File (case insensitive) does NOT exist: ${FILE}" 
fi