The following Bash script isail:
DATA=fred
echo ${DATA:1:1}
我期望它印刷“r”,但我发现的是“Bad替代”错误。
是否有某种类型的开关,我是否需要使用才能使变式的扩张汇合。
卡车
无,但你必须保证,它会用ash子,而不是其他壳。
bash script.sh
......
#!/bin/bash
......
这不是一个伟大的解决办法,而工作是:
TEST=`echo "${DATA}" | sed -r s|^.(.).*$|1| `
感谢Ignacio的建议
I m attempting to write a bash script to parse out the following log file and give me a list of CURRENT players in the room (so ignoring players that left, but including players that may have rejoined)...
How can I check the file encoding in a shell script? I need to know if a file is encoded in utf-8 or iso-8859-1. Thanks
I like to write bash shell scripts on my iPhone, put them in an app folder with an icon, plist, etc., so they execute like apps by tapping their icon on SpringBoard. This is not interactive like ...
From a programming standpoint, when you set the bash shell to use vi or emacs via set -o vi or set -o emacs What is actually going on here? I ve been reading a book where it claims the bash shell ...
I am construcing a command in bash dynamically. This works fine: COMMAND="java myclass" ${COMMAND} Now I want to dynamically construct a command that redirectes the output: LOG=">> myfile.log ...
I want perform sha1sum file1 and sha1sum file2 and perform bitwise OR operation with them using bash. Output should be printable i.e 53a23bc2e24d039 ... (160 bit) How can I do this? I know echo $(( ...
I m 试图撰写一个双面文字,处理一个文件清单,其名字在投入档案中每栏一栏储存,就像一个一样。
Is it possible to set the Screen Title using a shell script? I thought about something like sending the key commands ctrl+A shift-A Name enter I searched for about an hour on how to emulate ...