Linux C notes

Finally open a blog, after a busy exam week, forget the almost
Features of Linux 1. Multi-User 2. Multi-tasking 3. Multi-platform 4. Good user interface 5. Powerful network function 6. Safe, stable and efficient 7. Good portability 8. Open and free
Major releases of Linux: Fedora Core, Red Hat Linux,debian Linux and Red Flag Linux, etc.
Common commands for Linux
1. Shutdown (System shutdown, restart, and logout)
(1) Shut down the system
Shutdown-h now
Init 0
Telinit 0
(2) Restart
Shutdown-r now
Reboot
(3) write-off Logout

2. Files and directories
(1). Change the current directory CD
Cd/home Enter '/home ' directory '
Cd.. Return to the top level directory
Cd.. /.. Return to the top level two directory
CD into the personal home directory
CD ~ Enter the user's home directory
CD-Return to the last directory
(2) Show work path pwd
(3) Display directory or file information ls
ls to view the files in the directory
Ls-f viewing files in a directory
Ls-l displaying details of files and directories
Ls-a Show all files, including hidden files
LS *[0-9]* displays filenames and directory names that contain numbers
Ls-t sorting results by modified time, new catalog file in front
(4) tree structure showing files and directories starting with the root directory
Tree
Lstree
(5) Create a folder mkdir
mkdir dir1 Create a directory called ' Dir1 '
mkdir dir1 DIR2 Create two directories at a time
Mkdir-p/tmp/dir1/dir2 Create a directory tree
(6) Delete RM
Rm-f file1 Delete a file called ' File1 '
RmDir dir1 Delete a directory called ' Dir1 '
RM-RF Dir1 Delete a directory called ' Dir1 ' and delete its contents at the same time
RM-RF dir1 DIR2 Delete two directories and their contents at the same time
(7) Moving MV
MV Dir1 New_dir Renaming/Moving a directory
(8) Copy CP
CP file1 file2 Copy a file
CP dir/*. Copy all files under a directory to the current working directory
Cp-a/tmp/dir1. Copy a directory to the current working directory
Cp-a dir1 dir2 Copy a directory

(9) Modify the timestamp of a file or directory touch-t 0712250000 file1
(10) View file contents cat
(11) View file contents and reverse output TAC
(12) Viewing the contents of a File Page view less
(13) View non-text file od

3. File Search
Find/-name file1 from '/' to the root file system to search for files and directories
Find/-user User1 search for files and directories belonging to user ' User1 '
Find/home/user1-name \*.bin in directory '/home/user1 ' search for files with '. Bin '
Locate \*.ps looking for files ending with '. ps '-run the ' updatedb ' command first



GCC Common options
-E tells GCC to stop the compilation process after preprocessing
-C cppoutput or source file compiled into target code (. O)
-G generates standard debug information.
-ggdb generate a lot of debugging information that only GDB can recognize
-O Output_filename
-W turns off all warnings.
-Q lets GCC display each function encountered during compilation and provides profiling information about the time it takes to compile each function
-save-temps Save intermediate files generated during compilation

Linux C notes