linux - 如果文件具有 Windows 行结尾，请将其更改为 Linux 行结尾，否则不执行任何操作

Question

我想写一个 if 语句，如果文件有 Windows 行结尾，则将其更改为 Linux 行结尾，否则什么也不做

这是带有 Windows 行结尾的文件 ^M或\r\n

$ cat -v  file.csv | head
"Rec_Open_Date","MSISDN","IMEI","Data_Volume_Bytes","Device_Manufacturer","Device_Model","Product_Description"^M
"2015-10-06","427","060","137765","Samsung Korea","Samsung SM-G900I","$39 Plan"^M
"2015-10-06","592","620","0","Apple Inc","Apple iPhone 6 (A1586)","PREPAY  STD - TRIAL - #16"^M
"2015-10-06","007","290","0","Apple Inc","Apple iPhone 6 (A1586)","PREPAY PLUS - $0 -"^M
"2015-10-06","592","050","48836832","Apple Inc","Apple iPhone 5S (A1530)","Talk and Text Connect Flexi Plan"^M
"2015-10-06","409","720","113755347","Samsung Korea","Samsung SM-G360G","$29 CARRYOVER PLAN"^M
"2015-10-06","742","620","19840943","Apple Inc","Apple iPhone S (A1530)","PREPAY STD - $0 - #2"^M
"2015-10-06","387","180","0","HUAWEI Technologies Co Ltd","HUAWEI HUAWEI G526-L11","PREPAY STD - $1 - #4"^M
"2015-10-06","731","570","2258243","Samsung Korea","Samsung SM-N910U","Business Freedom"^M
"2015-10-06","556","910","13332272","Samsung Korea","Samsung GT-I9505","$49 Plan"^M

这是将其转换为 linux 行结尾的代码 \n :

  $ awk 'sub("\r$", "")' file.csv | head | cat -v
    "Rec_Open_Date","MSISDN","IMEI","Data_Volume_Bytes","Device_Manufacturer","Device_Model","Product_Description"
    "2015-10-06","427","060","137765","Samsung Korea","Samsung SM-G900I","$39 Plan"
    "2015-10-06","592","620","0","Apple Inc","Apple iPhone 6 (A1586)","PREPAY  STD - TRIAL - #16"
    "2015-10-06","007","290","0","Apple Inc","Apple iPhone 6 (A1586)","PREPAY PLUS - $0 -"
    "2015-10-06","592","050","48836832","Apple Inc","Apple iPhone 5S (A1530)","Talk and Text Connect Flexi Plan"
    "2015-10-06","409","720","113755347","Samsung Korea","Samsung SM-G360G","$29 CARRYOVER PLAN"
    "2015-10-06","742","620","19840943","Apple Inc","Apple iPhone S (A1530)","PREPAY STD - $0 - #2"
    "2015-10-06","387","180","0","HUAWEI Technologies Co Ltd","HUAWEI HUAWEI G526-L11","PREPAY STD - $1 - #4"
    "2015-10-06","731","570","2258243","Samsung Korea","Samsung SM-N910U","Business Freedom"
    "2015-10-06","556","910","13332272","Samsung Korea","Samsung GT-I9505","$49 Plan"

这是我的基本 if 语句，我只是不确定如何从行结尾得到 true 或 false:有人可以建议我如何做到这一点吗？

if [ $1 -gt 100 ]  ## line ending =^M
then
awk 'sub("\r$", "")' file.csv   ## remove the windows line endings
fi

据我所知， self 注释 Windows 行结尾可以是 ^M , \r\n或CRLF 。 linux 行结尾可以是 \n LF .

---

编辑1

想想this这就是我正在寻找的。

$  eol=$(cat -v  file.csv | head -n1 | grep -o '..$')
$  echo "$eol"
^M
$ if [ "$eol" = "^M" ]; then echo "true"; fi
true
$ if [ "$eol" = "^M" ]; then echo "true"; else echo "false"; fi
true

我会把awk 'sub("\r$", "")' file.csv放在哪里正如我的真实陈述

Answer 1

使用vim将文件格式更改为Unix，例如

vim file.txt <<EOF
:set fileformat=unix
ZZ
EOF

如果文件已经是 Unix 格式，上面的代码将使文件保持不变。