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
哇……这是一个老问题，但我认为这是一个相当优雅的答案。首先，使用shell参数展开(参见shell参数展开)将每个点分隔的版本转换为自己的数组。
v1="05.2.3" # some evil examples that work here
v2="7.001.0.0"
declare -a v1_array=(${v1//./ })
declare -a v2_array=(${v2//./ })
现在，这两个数组将版本号按优先级顺序作为数值字符串。上面的许多解决方案都是从这里开始的，但它们都源于这样的观察:版本字符串只是一个具有任意基数的整数。我们可以测试找到第一个不相等的数字(就像strcmp对字符串中的字符所做的那样)。
compare_version() {
declare -a v1_array=(${1//./ })
declare -a v2_array=(${2//./ })
while [[ -nz $v1_array ]] || [[ -nz $v2_array ]]; do
let v1_val=${v1_array:-0} # this will remove any leading zeros
let v2_val=${v2_array:-0}
let result=$((v1_val-v2_val))
if (( result != 0 )); then
echo $result
return
fi
v1_array=("${v1_array[@]:1}") # trim off the first "digit". it doesn't help
v2_array=("${v2_array[@]:1}")
done
# if we get here, both the arrays are empty and neither has been numerically
# different, which is equivalent to the two versions being equal
echo 0
return
}
如果第一个版本小于第二个版本，则返回负数，如果相等则返回零，如果第一个版本大于第二个版本则返回正数。一些输出:
$ compare_version 1 1.2
-2
$ compare_version "05.1.3" "5.001.03.0.0.0.1"
-1
$ compare_version "05.1.3" "5.001.03.0.0.0"
0
$ compare_version "05.1.3" "5.001.03.0"
0
$ compare_version "05.1.3" "5.001.30.0"
-27
$ compare_version "05.2.3" "7.001.0.0"
-2
$ compare_version "05.1.3" "5.001.30.0"
-27
$ compare_version "7.001.0.0" "05.1.3"
2
堕落的例子，”。2”或“3.0.”不起作用(未定义的结果)，并且如果'. 2 '旁边出现非数字字符。它可能会失败(还没有测试)，但肯定是没有定义的。因此，这应该与一个消毒函数或适当的检查有效的格式相匹配。此外，我相信通过一些调整，可以在没有太多额外负担的情况下使其更加健壮。
其他回答
这个怎么样?似乎有用?
checkVersion() {
subVer1=$1
subVer2=$2
[ "$subVer1" == "$subVer2" ] && echo "Version is same"
echo "Version 1 is $subVer1"
testVer1=$subVer1
echo "Test version 1 is $testVer1"
x=0
while [[ $testVer1 != "" ]]
do
((x++))
testVer1=`echo $subVer1|cut -d "." -f $x`
echo "testVer1 now is $testVer1"
testVer2=`echo $subVer2|cut -d "." -f $x`
echo "testVer2 now is $testVer2"
if [[ $testVer1 -gt $testVer2 ]]
then
echo "$ver1 is greater than $ver2"
break
elif [[ "$testVer2" -gt "$testVer1" ]]
then
echo "$ver2 is greater than $ver1"
break
fi
echo "This is the sub verion for first value $testVer1"
echo "This is the sub verion for second value $testVer2"
done
}
ver1=$1
ver2=$2
checkVersion "$ver1" "$ver2"
我不喜欢这些解决方案，因为它们漏洞百出、不可移植等等。
我(目前)努力提出一个更好的解决方案……src: version_compare(),测试
Sorta-copied /贴在这里……
来源:
##
# Compare two versions.
#
# **Usage:** version_compare version1 operator version2
#
# - operator:
#
# + ``lesser_than``, ``-lt``, ``<``
# + ``lesser_than_or_equal``, ``-le``, ``<=``
# + ``greater_than``, ``-gt``, ``>``
# + ``greater_than_or_equal``, ``-ge``, ``>=``
# + ``equal``, ``-eq``, ``==``
# + ``not_equal``, ``-ne``, ``!=``
#
# - version{1,2}: arbitrary version strings to compare
#
# **Version Format:** ``[0-9]+($VERSION_SEPARATOR[0-9]+)*`` (i.e. 1, 1.0, 90, 1.2.3.4)
#
# **Returns:** true if comparison statement is correct
##
version_compare() {
_largest_version "$1" "$3"; _cmp="$(printf '%s' "$?")"
# Check for valid responses or bail early
case "$_cmp" in
1|0|2) :;;
*) _die "$_cmp" 'version comparison failed';;
esac
# The easy part
case "$2" in
'lesser_than'|'-lt'|'<')
[ "$_cmp" = '2' ] && return 0
;;
'lesser_or_equal'|'-le'|'<=')
[ "$_cmp" = '0' ] && return 0
[ "$_cmp" = '2' ] && return 0
;;
'greater_than'|'-gt'|'>')
[ "$_cmp" = '1' ] && return 0
;;
'greater_or_equal'|'-ge'|'>=')
[ "$_cmp" = '1' ] && return 0
[ "$_cmp" = '0' ] && return 0
;;
'equal'|'-eq'|'==')
[ "$_cmp" = '0' ] && return 0
;;
'not_equal'|'-ne'|'!=')
[ "$_cmp" = '1' ] && return 0
[ "$_cmp" = '2' ] && return 0
;;
*) _die 7 'Unknown operatoration called for version_compare().';;
esac
return 1
}
##
# Print a formatted (critical) message and exit with status.
#
# **Usage:** _die [exit_status] message
#
# - exit_status: exit code to use with script termination (default: 1)
# - message: message to print before terminating script execution
##
_die() {
# If first argument was an integer, use as exit_status
if [ "$1" -eq "$1" ] 2>/dev/null; then
_exit_status="$1"; shift
else
_exit_status=1
fi
printf '*** CRITICAL: %s ***\n' "$1"
exit "$_exit_status"
}
##
# Compare two versions.
# Check if one version is larger/smaller/equal than/to another.
#
# **Usage:** _largest_version ver1 ver2
#
# Returns: ($1 > $2): 1 ; ($1 = $2): 0 ; ($1 < $2): 2
# [IOW- 1 = $1 is largest; 0 = neither ; 2 = $2 is largest]
##
_largest_version() (
# Value used to separate version components
VERSION_SEPARATOR="${VERSION_SEPARATOR:-.}"
for _p in "$1" "$2"; do
[ "$(printf %.1s "$_p")" = "$VERSION_SEPARATOR" ] &&
_die 7 'invalid version pattern provided'
done
# Split versions on VER_SEP into int/sub
_v="$1$2"
_v1="$1"
_s1="${1#*$VERSION_SEPARATOR}"
if [ "$_v1" = "$_s1" ]; then
_s1=''
_m1="$_v1"
else
_m1="${1%%$VERSION_SEPARATOR*}"
fi
_v2="$2"
_s2="${2#*$VERSION_SEPARATOR}"
if [ "$_v2" = "$_s2" ]; then
_s2=''
_m2="$_v2"
else
_m2="${2%%$VERSION_SEPARATOR*}"
fi
# Both are equal
[ "$_v1" = "$_v2" ] && return 0
# Something is larger than nothing (30 < 30.0)
if [ -n "$_v1" ] && [ ! -n "$_v2" ]; then
return 1
elif [ ! -n "$_v1" ] && [ -n "$_v2" ]; then
return 2
fi
# Check for invalid
case "$_m1$_m2" in
*[!0-9]*)
_die 7 'version_compare called with unsupported version type'
;;
esac
# If a ver_sep is present
if [ "${_v#*$VERSION_SEPARATOR}" != "$_v" ]; then
# Check for a larger "major" version number
[ "$_m1" -lt "$_m2" ] && return 2
[ "$_m1" -gt "$_m2" ] && return 1
# Compare substring components
_largest_version "$_s1" "$_s2"; return "$?"
else
# Only integers present; simple integer comparison
[ "$_v1" -lt "$_v2" ] && return 2
[ "$_v1" -gt "$_v2" ] && return 1
fi
)
测试:
# Simple test of all operators
( version_compare '1' 'lesser_than' '2' ); [ "$?" = '0' ] || return 1
( version_compare '2' 'equal' '2' ); [ "$?" = '0' ] || return 1
( version_compare '3' 'not_equal' '1' ); [ "$?" = '0' ] || return 1
( version_compare '2' 'greater_than' '1' ); [ "$?" = '0' ] || return 1
( version_compare '1' '-lt' '2' ); [ "$?" = '0' ] || return 1
( version_compare '2' '-eq' '2' ); [ "$?" = '0' ] || return 1
( version_compare '3' '-ne' '1' ); [ "$?" = '0' ] || return 1
( version_compare '2' '-gt' '1' ); [ "$?" = '0' ] || return 1
# Semver test of primary operators (expect true)
( version_compare '7.0.1' '-lt' '7.0.2' ); [ "$?" = '0' ] || return 1
( version_compare '7.0.2' '-eq' '7.0.2' ); [ "$?" = '0' ] || return 1
( version_compare '3.0.2' '-ne' '2.0.7' ); [ "$?" = '0' ] || return 1
( version_compare '7.0.2' '-gt' '7.0.1' ); [ "$?" = '0' ] || return 1
# Semver test of primary operators (expect false)
( version_compare '7.0.2' '-lt' '7.0.1' ); [ "$?" = '1' ] || return 1
( version_compare '3.0.2' '-eq' '2.0.7' ); [ "$?" = '1' ] || return 1
( version_compare '7.0.2' '-ne' '7.0.2' ); [ "$?" = '1' ] || return 1
( version_compare '7.0.1' '-gt' '7.0.2' ); [ "$?" = '1' ] || return 1
# Mismatched version strings (expect true)
( version_compare '7' '-lt' '7.1' ); [ "$?" = '0' ] || return 1
( version_compare '3' '-ne' '7.0.0' ); [ "$?" = '0' ] || return 1
( version_compare '7.0.1' '-gt' '7' ); [ "$?" = '0' ] || return 1
# Mismatched version strings (expect false)
( version_compare '7.0.0' '-eq' '7.0' ); [ "$?" = '1' ] || return 1
# Invalid operation supplied
( version_compare '2' '-inv' '1' >/dev/null ); [ "$?" = '7' ] || return 1
# Invalid version formats
( version_compare '1..0' '==' '1.0' >/dev/null ); [ "$?" = '7' ] || return 1
( version_compare '1.0' '==' '1..0' >/dev/null ); [ "$?" = '7' ] || return 1
( version_compare '1.0' '==' '1.0b7' >/dev/null ); [ "$?" = '7' ] || return 1
( version_compare '1.0a' '==' '1.0' >/dev/null ); [ "$?" = '7' ] || return 1
# "how does that handle comparing 10.0.0 (not a number) to 2.0 (a number)?"
( version_compare '10.0.0' '-lt' '2.0' ); [ "$?" = '1' ] || return 1
( version_compare '10.0' '-gt' '2.0.0' ); [ "$?" = '0' ] || return 1
# not less/greater-than... but equal
( version_compare '7' '-lt' '7' ); [ "$?" = '1' ] || return 1
( version_compare '7' '-gt' '7' ); [ "$?" = '1' ] || return 1
# String vs. numerical comparison
( version_compare '1.18.1' '-gt' '1.8.1' ); [ "$?" = '0' ] || return 1
# Random tests found on the internet
( version_compare '1' '==' '1' ); [ "$?" = '0' ] || return 1
( version_compare '2.1' '<' '2.2' ); [ "$?" = '0' ] || return 1
( version_compare '3.0.4.10' '>' '3.0.4.2' ); [ "$?" = '0' ] || return 1
( version_compare '4.08' '<' '4.08.01' ); [ "$?" = '0' ] || return 1
( version_compare '3.2.1.9.8144' '>' '3.2' ); [ "$?" = '0' ] || return 1
( version_compare '3.2' '<' '3.2.1.9.8144' ); [ "$?" = '0' ] || return 1
( version_compare '1.2' '<' '2.1' ); [ "$?" = '0' ] || return 1
( version_compare '2.1' '>' '1.2' ); [ "$?" = '0' ] || return 1
( version_compare '5.6.7' '==' '5.6.7' ); [ "$?" = '0' ] || return 1
( version_compare '1.01.1' '==' '1.1.1' ); [ "$?" = '0' ] || return 1
( version_compare '1.1.1' '==' '1.01.1' ); [ "$?" = '0' ] || return 1
( version_compare '1' '!=' '1.0' ); [ "$?" = '0' ] || return 1
( version_compare '1.0.0' '!=' '1.0' ); [ "$?" = '0' ] || return 1
如果它只是想知道一个版本是否比另一个版本低，我会检查sort——version-sort是否会改变我的版本字符串的顺序:
string="$1
$2"
[ "$string" == "$(sort --version-sort <<< "$string")" ]
如果你知道字段的数量，你可以用-k,n,n，得到一个超级简单的解
echo '2.4.5
2.8
2.4.5.1
2.10.2' | sort -t '.' -k 1,1 -k 2,2 -k 3,3 -k 4,4 -g
2.4.5
2.4.5.1
2.8
2.10.2
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>。
