Linux Basics

user@host:/tmp/test_dir$ ls    # List files and directories in the current directory
a.txt  b
user@host:/tmp/test_dir$ ls -l  # List detailed information about files and directories: permissions, Owner, Group, and creation/update time
total 4
-rw-rw-r-- 1 root root 0 Nov 9 10:50 a.txt
drwxrwxr-x 2 root root 4096 Nov 9 10:50 b

user@host:/tmp$ mkdir test_dir   # Create a new directory named test_dir
user@host:/tmp$ cd test_dir/     # Enter the test_dir directory
user@host:/tmp/test_dir$

user@host:/tmp/test_dir$ cd ../test_dir/   # Go to the test_dir directory which is in the parent directory
user@host:/tmp$

user@host:~$ pwd
/root/
user@host:~$

user@host:/tmp# mv test_dir/ test_directory   # Rename the directory test_dir to test_directory; this also applies to renaming files
user@host:/tmp# cd test_directory/
user@host:/tmp/test_directory#

user@host:/tmp/test_directory# mkdir a b     # Create two directories named a and b
user@host:/tmp/test_directory# ls
a  b
user@host:/tmp/test_directory# mv a b/       # Move a into the directory b. If directory b does not exist, this command would rename a to b
user@host:/tmp/test_directory# tree
.
└── b
    └── a

user@host:/tmp/test_directory$ mkdir a b     # Create two directories named a and b
user@host:/tmp/test_directory$ ls
a  b
user@host:/tmp/test_directory$ cp -r a b       # Copy directory a into directory b, with -r indicating recursive copy
user@host:/tmp/test_directory$ tree
.
├── a
└── b
    └── a

user@host:/tmp/test_directory$ ls
a.txt  folder
user@host:/tmp/test_directory$ rm -rf folder   
user@host:/tmp/test_directory$ rm -rf folder/*   # The asterisk (*) is a wildcard, representing all files and folders within the folder

export PATH=/x/x/x/miniconda3/bin:$PATH

export LD_LIBRARY_PATH=/usr/local/cuda/lib64:$LD_LIBRARY_PATH

#If you don't have zip installed, you can install it using:
apt-get update && apt-get install -y zip
#To compress a directory into a .zip file:
user@host:/tmp$ zip -r dir.zip test_directory/   # Compress the test_directory into a file named dir.zip
#To decompress a .zip file:
user@host:/tmp$ unzip dir.zip   # Decompress the dir.zip file

#The tar command is used for archiving and compressing files. The parameters c stands for create (compress), x for extract (decompress), and z for gzip compression/decompression.
#To compress a directory into a .tar.gz file:
user@host:/tmp$ tar czf dir.tar.gz test_directory/   # Compress the test_directory into a file named dir.tar.gz
#To decompress a .tar.gz file:
user@host:/tmp$ tar xzf dir.tar.gz   # Decompress the dir.tar.gz file
tar can also be used to compress and decompress other formats of archives, such as bz2.

#To compress a directory into a .tar.bz2 file:
user@host:/tmp$ tar cjf dir.tar.bz2 test_directory/   # Compress the test_directory into a file named dir.tar.bz2
#To decompress a .tar.bz2 file:
user@host:/tmp$ tar xjf dir.tar.bz2   # Decompress the dir.tar.bz2 file

root@container-5e3e11aeb4-948a17b1:~# ps -ef 
UID          PID    PPID  C STIME TTY          TIME CMD
root           1       0  0 14:04 ?        00:00:00 bash /init/boot/boot.sh
root          58      48  8 14:04 ?        00:00:03 /root/miniconda3/bin/python /root/miniconda3/bin/jupyter-lab --allow-root
root          60      48  0 14:04 ?        00:00:00 /usr/sbin/sshd -D
root          61      48 10 14:04 ?        00:00:04 /root/miniconda3/bin/python /root/miniconda3/bin/tensorboard --host 0.0.0.0 --port 6006 --logdir /root/tf-logs
root         146      61  0 14:04 ?        00:00:00 /root/miniconda3/lib/python3.8/site-packages/tensorboard_data_server/bin/server --logdir=/root/tf-logs
root         402     338 99 14:05 pts/0    00:00:06 python tensorflow2.x-test.py

root@container-5e3e11aeb4-948a17b1:~# kill -9 402
root@container-5e3e11aeb4-948a17b1:~#

user@host:/tmp$ python train.py    # Normally, logs are output to stdout/stderr.
Epoch.1 Iter 20
Epoch.1 Iter 40
Epoch.1 Iter 50
...

user@host:/tmp$ python train.py > ./train.log 2>&1  # Redirect logs from stdout/stderr to the train.log file. In the command 2>&1, 2 represents stderr, and 1 represents stdout. The &1 can be thought of as taking the address, similar to C language.

user@host:/tmp$ cat ./train.log    # Print the contents of the train.log file to stdout. cat (Concatenate FILE(s) to standard output.)
Epoch.1 Iter 20
Epoch.1 Iter 40
Epoch.1 Iter 50
...

user@host:/tmp$ python train.py > ./train.log 2>&1 &   # If you add an & at the end, it runs in the background. You can also consider using it in conjunction with nohup.

user@host:~$ pwd
/root/
user@host:~$ ls
train.py  gpuhub-tmp  gpuhub-nas
user@host:~$ cp -r train.py gpuhub-nas/   # Copy the train.py file into the network drive