bash 脚本中的 mkdir 错误
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mkdir error in bash script
提问by Dónal
The following is a fragment of a bash script that I'm running under cygwin on Windows:
以下是我在 Windows 上的 cygwin 下运行的 bash 脚本的片段：
deployDir=/cygdrive/c/Temp/deploy
timestamp=`date +%Y-%m-%d_%H:%M:%S`
deployDir=${deployDir}/$timestamp
if [ ! -d "$deployDir" ]; then
echo "making dir $deployDir"
mkdir -p $deployDir
fi
This produces output such as:
这会产生输出，例如：
making dir /cygdrive/c/Temp/deploy/2010-04-30_11:47:58
mkdir: missing operand
Try `mkdir --help' for more information.
However, if I type /cygdrive/c/Temp/deploy/2010-04-30_11:47:58on the command-line it succeeds, why does the same command not work in the script?
但是，如果我/cygdrive/c/Temp/deploy/2010-04-30_11:47:58在命令行上输入它成功，为什么相同的命令在脚本中不起作用？
Thanks, Don
谢谢，唐
回答by Bert F
Change:
改变：
mkdir -p $deploydir
to
到
mkdir -p "$deployDir"
Like most Unix shells (maybe even all of them), Bourne (Again) Shell (sh/bash) is case-sensitive. The dir var is called deployDir(mixed-case) everywhere except for the mkdircommand, where it is called deploydir(all lowercase). Since deploydir(all lowercase) is a considered distinct variable from deployDir(mixed-case) and deplydir(all lowercase) has never had a value assigned to it, the value of deploydir(all lowercase) is empty string ("").
像大多数 Unix shell（甚至可能是所有 shell）一样，Bourne (Again) Shell (sh/bash) 区分大小写。dir var 在deployDir任何地方都被调用（混合大小写），除了mkdir命令，在那里它被调用deploydir（全部小写）。由于deploydir（全小写）被认为是与deployDir（混合大小写）不同的变量，并且deplydir（全小写）从未分配过值，因此deploydir（全小写）的值是空字符串（“”）。
Without the quotes (mkdir $deploydir), the line effectively becomes mkdir(just the command without the required operand), thus the error mkdir: missing operand.
没有引号 ( mkdir $deploydir)，该行实际上变为mkdir（只是没有所需操作数的命令），因此错误mkdir: missing operand.
With the quotes (mkdir "$deploydir"), the line effectively becomes mkdir ""(the command to make a directory with the illegal directory name of empty string), thus the error mkdir: cannot create directory'.
使用引号 ( mkdir "$deploydir")，该行有效地变为mkdir ""（使用空字符串的非法目录名称创建目录的命令），因此错误mkdir: cannot create directory'.
Using the form with quotes (mkdir "$deployDir") is recommended in case the target directory name includes spaces.
如果mkdir "$deployDir"目标目录名称包含空格，建议使用带引号 ( )的形式。
回答by Paul R
Change:
改变：
mkdir -p $deploydir
to
到
mkdir -p "$deploydir"
回答by unwind
You can't have colons in file names on Windows, for obvious reasons.
出于显而易见的原因，Windows 上的文件名中不能有冒号。
