? [-f file] Determine whether it is a normal file and exist
? [-d file] Determine whether it is a directory and exist
? [-e file] Determine whether a file or directory exists
>? [-r file] Determin
Category: Unix
The UNIX operating system (Eunice) is a powerful multi-user, multi-tasking operating system that supports multiple processor architectures. According to the classification of the operating system, it is a time-sharing operating system. It was first developed by KenThompson, Dennis Ritchie and Douglas McIlroy in 1969 Developed in AT&T’s Bell Labs in the year. At present, its trademark rights are owned by the International Open Standards Organization, and only UNIX systems that conform to a single UNIX specification can use the name UNIX, otherwise it can only be called UNIX-like (UNIX-like)
Shell script – GREP and regular expressions
grep command
1, grep program: Linux Three Musketeers–grep, awk, sed
2, GrepL: text line filtering tool
Awk: report generator (formatting text output)
3, grep contains three
Shell write progress bar
test.sh
#!/bin/bash
i=0
bar=‘‘
label=(“|” “/” “-” “\\< span style="color: #800000;">“)
while [$i -le 100]
do
printf “[\e[43;46;lm%-100s \e[0m][%d%%][%c]\r” “$bar” “$i” “${label[i%4]}”
Shell Programming
1. Variable A=8
echo $A
echo “$0 $1 $2”
echo “$*”
echo “[email protected]”
echo “$#”
S=$[(2+3)*4]
= String Compare
-lt less thanless than
-le l
How to delete a particular row that appears in the Vim file
I want to delete a line: this is an example, it appears multiple times in the file. What should I do?
Thank you,
AI Lisa
:g/This is an example/d
I want to delete a line: this is a
Shell string stitching
test.sh
#!/bin/bash
your_name=”runoob”
# Use double quotes to splice
greeting=”hello, “$your_name” !”
greeting_1=”hello, ${your_name} ! ”
echo $greeting $greeting_1
# Use single quotes
SHELL variable foundation detailed
1. Introduction to variables Variables are places where data is temporarily stored and data tags. The stored data exists in the memory space, and the data corresponding to the variable can be retri
Use of the function in the shell
function is a script code block, you can name it yourself, and you can use this function anywhere in the script. If you want this function, just call the name of the function. The advantage of usin
Bash or Python for changing file spacing
I have a set of 10,000 files. In all of them, the second line looks like:
AAA 3.429 3.84 So there is only one space between AAA and the other two columns (required). The rest of the lines on
Self-built NuGet package
Some internally used components, unified management, automatic upgrade.
1. Create an empty asp.net Web project, add a reference to NuGet.Server, and publish this website to IIS. 2. Install NuG