目录

$ df -h
Filesystem      Size  Used Avail Use% Mounted on
udev            126G     0  126G   0% /dev
tmpfs            26G  4.0M   26G   1% /run
/dev/sda2       548G   50G  471G  10% /
tmpfs           126G     0  126G   0% /sys/fs/cgroup
/dev/sda1       511M  7.9M  504M   2% /boot/efi
/dev/sdb1       2.0T  4.7G  1.9T   1% /data

字母小写转大写

$ df -h | tr [:lower:] [:upper:]

FILESYSTEM      SIZE  USED AVAIL USE% MOUNTED ON
UDEV            126G     0  126G   0% /DEV
TMPFS            26G  4.0M   26G   1% /RUN
/DEV/SDA2       548G   50G  471G  10% /
TMPFS           126G     0  126G   0% /SYS/FS/CGROUP
/DEV/SDA1       511M  7.9M  504M   2% /BOOT/EFI
/DEV/SDB1       2.0T  4.7G  1.9T   1% /DATA

$ df -h | tr a-z A-Z

字母大写转小写

$ df -h | tr [:upper:] [:lower:]
$ df -h | tr A-Z a-z

空格转换成逗号(,)

$ df -h | tr -s ' ' ','

Filesystem,Size,Used,Avail,Use%,Mounted,on
udev,126G,0,126G,0%,/dev
tmpfs,26G,4.0M,26G,1%,/run
/dev/sda2,548G,50G,471G,10%,/
tmpfs,126G,0,126G,0%,/sys/fs/cgroup
/dev/sda1,511M,7.9M,504M,2%,/boot/efi
/dev/sdb1,2.0T,4.7G,1.9T,1%,/data
  • -s 重复的字符序列

花括号替换圆括号

$ echo '{Hello}' | tr '{}' '()'

(Hello)

删除

删除字符

$ echo 'Hello world!' | tr -d hello
H wrd!

删除数字

$ echo "my ID is 73535" | tr -d [:digit:]

my ID is

删除除数字以外的字符

$ echo "my ID is 73535" | tr -cd [:digit:]

73535

参考资料