* match the pattern ~ telda | pipe r recursivly w write f force i bang v print log
Terminal tips
tab hit to auto completereset resets all terminal default look & othersclear clean terminal window & you can scroll for old writings Ctrl+L clean terminal window & you can scroll for old writings!x repeats the most recent command starting with xhistory grape all the commands you wrote entirely the history of the bash shellman X show you the manual of command ”X”echo “word” print “word” on the screen echo “word” > name put “word” in a new file called name echo “word” >> name adds “word” + previous words into file called name./mario < inputFile takes data from inputFile to use it as input into mario filehistory | grep ls takes all the history outputs & feeding it to grep command so that grep recognizes the ls words in itcat fileName looks inside that filename, Prints current file contents to stdout; semi colon allow us to run many programs in same line, Just divide between them by a semi colonwhich commandName check if you have a program installed that uses that commandName
COMMANDS
Files & Directories
list
lslist the folders & files in this directory ls -l list files + more info + permissions ls -a list the folders + Hidden ls -la list the folders + Hidden + Permissions
cd change directory
cdlocation change directory cd ~/location go back till this location directory cd .. up one level location cd . takes me to the current Directory cd - takes me to the last Directory I was in before the current cd ../directory1/directory2/ takes you to directory2 that's inside directory1pwf show you the current directory location details
cut & copy , create files & directories
mv fileName newFilename rename file mv anyFile anyFolder anyFile lastFolder moves everything in the lastFoldercp oldFile.c newFile.c copy the oldFile & name the newFiletouch filename create a new emty filename mkdir Name makes a new directory(folder) called Name rmdirName remove the directory if only it's empty
delete, remove files & directories
rm file.c remove the file with ask you first (only files) rm -f file.c -f flag forces removing file without Asking rm -r Name remove the directory rm -rf Name remove the directory & all it's files + f without Askingrm *1 remove the files & directories with pattern 1 in it's name rm * remove all the contents of the current directory rm -i -i flag requires user’s confirmationDANGEROUS: don't do it rm -rf ~ removes everything in home directory rm -rf / removes everything in root directory
search & find words, files, directories
grep
grep “wanted word” recognizes wanted word while typing grep “wanted word” X search for “wanted word” in X Location, files grep “wanted word” * search for “wanted word” in all files &foldersgrep -r search in directories & sub-directory
find
find . -name “cat” search for folder or file with the exact name “cat”find . -name “*cat” search for folder or file with after pattern name “cat”find . -name “cat*” search for folder or file with after pattern name “cat”find . -name *.c search for folder or file with .c extenction find . -type d search for all directories in the current directoryfind . -type f search for all files in the current directory
Text Editors
gedit & nano
gedit opens gedit & you can't use Terminal till you close Gedit gedit name.txt opens gedit & make file called namenano opens a bacic text Terminal Editor nanofilename opens filename in nano texteditor ALT+L turn off text-wrapping
vim filename opens filename in cim rich texteditor vi filename opens filename in cim rich texteditor
*PIPES*
redirect.c
int main() { string input = GetString(); printf("%s\n", input); }
stdout standard output
./redirect > file.txt saves the output to the file.txt & replace evetthing in file.txt./redirect >> file.txt Append (Adds) the output to the current contents in file.txt2> prints only error messages./redirect > /dev/null output will be discarded, Data Black hole
stdin standard input
./redirect < file.txt > file2.txt Get the input from file.txt & saves the output to the file2.txt & replace everything in file2.txtNotice We only have 1 GetString in redirect.c so it will take only 1 line input
Output of a program to Input of another program
hello.c
int main() { printf("Hello World\n"); }
command
./hello > input.txt Take hello output into input.txt./redirect < input.txt Take input.txt as an Input./hello > input.txt; ./redirect <input.txt same result of the first two just using one line
Output of a program on the “Pipe Left” to Input of another program on “Pipe Right”
pipeline
To avoid creating that extra file "input.txt" from previous example./hello | ./redirect same result as previous just using pipe
Combine Command lines using Pipeline
wc -l -l flag to count lines, wc to countls | wc -l combining ls command as stout to show the current files in directory, then use this result as stdin to ws -l to count the words, So we know how many files in this directorycat students.txt | sort Will get the stdin from cat and stdout to sort, result show them in alphabetical ordercat students.txt | sort | uniq > final.txt Saves all sorted without duplication names in final.txtsort < students.txt | uniq > final2.txt same result
Extras
operators
| or 0|0= 0, 0|1 = 1 ^ exclusively different or 0^0= 0, 0^1 = 1 ~ telda flipping operator from 0 to 1, 1 to 0 & And 0&0 = 0 , 1&0 = 0 << : shift operator 1<<7 = 10000000
echo
echo $? Echoes (prints) the exit value for the previous command. If it failed it will be different than zero (0). $ cd ~ $ echo $? > 0$ cd //whatever/ > bash: cd: //whatever/: No such file or directory $ echo $? > 1
clang file.c compile the file in c language, clang is a very basic c language compilerclang -ggdb3 -O0 -std=c99 -Wall -Werror soso.c -lm -o soso full clang = makemake file compile the file with all the clang flags
