Linux system commands
which: View the location of the command
which cd
find: View the location of the file
find starting path-name "File name to find"
find starting path-size +|- n [k|M|G]
find / -name test.txt
Find files larger than 100k
find / -size +100K
grep: Filter keywords from files
grep [-n] keyword file path
-n: Optional, indicating the line number of the matching line displayed in the results
grep "demo" test.txt
Use the pipe character "|", the following means: filter the position of the demo character from the test.txt file, the pipe character means: use the content on the left as the input on the right
cat test.txt | grep "demo"
wctotal
wc [-c -m -l -w] file path
| option | meaning |
|---|---|
| -c | Count the number of bytes |
| -m | Count the number of characters |
| -l | Count rows |
| -w | Count the number of words |
wc test.txt
echoOutput the specified content on the command line
echo output content
echo "hello Linux"
Use "`" to output in command form
echo `pwd`
Use the ">" redirection method to overwrite and write, as follows: write hello to the test.txt file
echo "hello" > test.txt
Use the ">>" redirection method to append writing, as follows: append hello to the test.txt file
echo "hello" >> test.txt
tailView file tail information
tail [-f -num] Linux path
| option | meaning |
|---|---|
| -f | Keep track of |
| -num | Count the number of characters |
Continue to track the tail content of the file. If there are changes, the status will be updated. Click ctrl+c to exit the program.
tail -f test.txt