是否有办法在bash上比较这些字符串,例如:2.4.5和2.8和2.4.5.1?


当前回答

下面是对顶部答案(Dennis的)的改进,它更简洁,并使用了不同的返回值方案,以便通过单个比较轻松实现<=和>=。它还比较不是[0-9]的第一个字符之后的所有内容。]因此1.0rc1 < 1.0rc2。

# Compares two tuple-based, dot-delimited version numbers a and b (possibly
# with arbitrary string suffixes). Returns:
# 1 if a<b
# 2 if equal
# 3 if a>b
# Everything after the first character not in [0-9.] is compared
# lexicographically using ASCII ordering if the tuple-based versions are equal.
compare_versions() {
    if [[ $1 == "$2" ]]; then
        return 2
    fi
    local IFS=.
    local i a=(${1%%[^0-9.]*}) b=(${2%%[^0-9.]*})
    local arem=${1#${1%%[^0-9.]*}} brem=${2#${2%%[^0-9.]*}}
    for ((i=0; i<${#a[@]} || i<${#b[@]}; i++)); do
        if ((10#${a[i]:-0} < 10#${b[i]:-0})); then
            return 1
        elif ((10#${a[i]:-0} > 10#${b[i]:-0})); then
            return 3
        fi
    done
    if [ "$arem" '<' "$brem" ]; then
        return 1
    elif [ "$arem" '>' "$brem" ]; then
        return 3
    fi
    return 2
}

为了解决@gammazero的评论,一个(我认为)与语义版本兼容的更长的版本是:

# Compares two dot-delimited decimal-element version numbers a and b that may
# also have arbitrary string suffixes. Compatible with semantic versioning, but
# not as strict: comparisons of non-semver strings may have unexpected
# behavior.
#
# Returns:
# 1 if a<b
# 2 if equal
# 3 if a>b
compare_versions() {
    local LC_ALL=C

    # Optimization
    if [[ $1 == "$2" ]]; then
        return 2
    fi

    # Compare numeric release versions. Supports an arbitrary number of numeric
    # elements (i.e., not just X.Y.Z) in which unspecified indices are regarded
    # as 0.
    local aver=${1%%[^0-9.]*} bver=${2%%[^0-9.]*}
    local arem=${1#$aver} brem=${2#$bver}
    local IFS=.
    local i a=($aver) b=($bver)
    for ((i=0; i<${#a[@]} || i<${#b[@]}; i++)); do
        if ((10#${a[i]:-0} < 10#${b[i]:-0})); then
            return 1
        elif ((10#${a[i]:-0} > 10#${b[i]:-0})); then
            return 3
        fi
    done

    # Remove build metadata before remaining comparison
    arem=${arem%%+*}
    brem=${brem%%+*}

    # Prelease (w/remainder) always older than release (no remainder)
    if [ -n "$arem" -a -z "$brem" ]; then
        return 1
    elif [ -z "$arem" -a -n "$brem" ]; then
        return 3
    fi

    # Otherwise, split by periods and compare individual elements either
    # numerically or lexicographically
    local a=(${arem#-}) b=(${brem#-})
    for ((i=0; i<${#a[@]} && i<${#b[@]}; i++)); do
        local anns=${a[i]#${a[i]%%[^0-9]*}} bnns=${b[i]#${b[i]%%[^0-9]*}}
        if [ -z "$anns$bnns" ]; then
            # Both numeric
            if ((10#${a[i]:-0} < 10#${b[i]:-0})); then
                return 1
            elif ((10#${a[i]:-0} > 10#${b[i]:-0})); then
                return 3
            fi
        elif [ -z "$anns" ]; then
            # Numeric comes before non-numeric
            return 1
        elif [ -z "$bnns" ]; then
            # Numeric comes before non-numeric
            return 3
        else
            # Compare lexicographically
            if [[ ${a[i]} < ${b[i]} ]]; then
                return 1
            elif [[ ${a[i]} > ${b[i]} ]]; then
                return 3
            fi
        fi
    done

    # Fewer elements is earlier
    if (( ${#a[@]} < ${#b[@]} )); then
        return 1
    elif (( ${#a[@]} > ${#b[@]} )); then
        return 3
    fi

    # Must be equal!
    return 2
}

其他回答

### the answer is does we second argument is higher
function _ver_higher {
        ver=`echo -ne "$1\n$2" |sort -Vr |head -n1`
        if [ "$2" == "$1" ]; then
                return 1
        elif [ "$2" == "$ver" ]; then
                return 0
        else
                return 1
        fi
}

if _ver_higher $1 $2; then
        echo higher
else
        echo same or less
fi

它非常简单和小。

可能没有普遍正确的方法来实现这一点。如果您正在尝试比较Debian包系统中的版本,请尝试dpkg——compare-versions <first> <relation> <second>。

与其编写冗长的代码使您的生活过于复杂,不如使用一些已经存在的东西。很多时候,当bash不够用时,python可以提供帮助。你仍然可以很容易地从bash脚本调用它(额外的好处:从bash到python的变量替换):

VERSION1=1.2.3
VERSION2=1.2.4

cat <<EOF | python3 | grep -q True
from packaging import version
print(version.parse("$VERSION1") > version.parse("$VERSION2"))
EOF

if [ "$?" == 0 ];  then
   echo "$VERSION1 is greater than $VERSION2"
else
   echo "$VERSION2 is greater or equal than $VERSION1"
fi

这里有更多信息:如何比较Python中的版本号?

function version_compare () {
  function sub_ver () {
    local len=${#1}
    temp=${1%%"."*} && indexOf=`echo ${1%%"."*} | echo ${#temp}`
    echo -e "${1:0:indexOf}"
  }
  function cut_dot () {
    local offset=${#1}
    local length=${#2}
    echo -e "${2:((++offset)):length}"
  }
  if [ -z "$1" ] || [ -z "$2" ]; then
    echo "=" && exit 0
  fi
  local v1=`echo -e "${1}" | tr -d '[[:space:]]'`
  local v2=`echo -e "${2}" | tr -d '[[:space:]]'`
  local v1_sub=`sub_ver $v1`
  local v2_sub=`sub_ver $v2`
  if (( v1_sub > v2_sub )); then
    echo ">"
  elif (( v1_sub < v2_sub )); then
    echo "<"
  else
    version_compare `cut_dot $v1_sub $v1` `cut_dot $v2_sub $v2`
  fi
}

### Usage:

version_compare "1.2.3" "1.2.4"
# Output: <

功劳归于@Shellman

我的观点是:

vercomp () {
    if [[ "${1}" == "${2}" ]]; then
        echo '0'
        return
    fi
    echo "${1}" | sed 's/\([0-9]\+\)\./\1\n/g' | {
        _RES_=-1
        for _VB_ in $(echo "${2}" | sed 's/\([0-9]\+\)\./\1\n/g'); do
            if ! read -r _VA_ || [[ "${_VB_}" -gt "${_VA_}" ]]; then
                _RES_=1
                break
            fi
        done
        read -r _VA_ && echo '-1' || echo "${_RES_}"
    }
}

语法:

vercomp VERSION_A VERSION_B

打印:

-1如果VERSION_A是最近的版本 如果两个版本相等,则为0 如果VERSION_B是最近的版本,则为1