Embedded Linux operating system
Introduction to Linux
1. Install Linux development environment
Vm virtual machine (PC simulation by means of software); Linux distributions (version issued to the user's), redhat (centos 7), ubuntu (18.04), deppin.
2.Linux introduction (POSIX, GPL, GNU)
1991 Linux0.1 GPL: the open source community
the GPL --Linux5.0
UNIX: Father's 1978-1979 C language: the father of Dennis Ritchie == unix (commercial software)
the POSIX standard: can (cross-platform condition Portable Operating System Interface )
the GNU program: GNU is not unix (excellent tool gcc gdb)
Linux use
1. user management command
su: switch the root; sudo: for more advanced permissions.
adduser: add new users; deluser: delete users.
passwd: change the password.
2. The file operation command
Linux a little philosophy: everything is a file.
Linux file classification: regular file (- at the beginning), catalog file (d), the device file (c: character device / b: block device), link file (l).
Linux special files: pipe file (p), the stack file (f), shared file (s).
Linux operating authority file: r: read, w: write, x: executable.
Permission Description (Group 3) :( current user, current user groups, other users).
chmod: modify file permissions.
touch: create a file; cat: view the file; rm: delete the file.
3. File editor
gedit: preparation of documents
gcc: compile the file
./a.out: executable file
4. Directory Operations
cd: enter the directory; cd ...: exit directory.
mkdir / mkdir -p: Create a directory
rm -r / rmdir: delete the directory
/: root directory - the parent directory of all files in
bin: system commands
sbin: Administrator command
dev: All device file system
etc: system All profiles
root: root user's working directory
home: the ordinary user's working directory
usr: Software (library file, header file) installed in the system
~: current user's working directory
5. The absolute and relative paths
absolute path: cd 0208
relative path: the root CD / 0208
6. The copy
copy files: cp
copy directory: -R & lt CP
7. the cut: Music Videos
8. the common commands
clear: clear screen
pwd: View the current path
tar cvzf: compressed files (extension files are compressed .tar.gz)
the tar xvzf: extracting file (to extract the specific path: tar xvzf -C path)
reboot: restart
shutdown: shutdown
LInux Development Tools
