bash Cheat Sheet by gregcheater via cheatography.com/26582/cs/7469/ - PDF document

bash Cheat Sheet by gregcheater via cheatography.com/26582/cs/7469/ basic bash commands bash redire ​ ctions (cont) control structure (case)  pwd : print working directory  command &>> file : redirect stdout and # patterns are file globing regex stderr to file. (creates the file if it doesn't exist  cd /path/ ​ to/dir : change direcotry case <ex ​ pre ​ ssi ​ on> in and append to the end it if it does exist) ​ ​ ​ ​ pat ​ tern1)  ls /dir/t ​ o/list : list directory content (default is  command < file : redirect stdin to file. ​ ​ ​ ​ ​ ​ ​ ​ [st ​ ate ​ ments] .)  command1 | command 2 : uses the output ​ ​ ​ ​ ​ ​ ​ ;; ​ ​ ​ -1 : display the content on one column of command1 as the input of command2 ​ ​ ​ ​ pat ​ tern2) ​ ​ ​ -l : display the content with long listing format ​ ​ ​ ​ ​ ​ ​ ​ [st ​ ate ​ ments] ​ ​ ​ -a : display the content of the directory file globbing regex ​ ​ ​ ​ ​ ​ ​ ;; (including hidden files)  \ : escape character. It deletes the ​ ​ ​ *) ​ ​ ​ -R : Display the content of the directory and signif ​ ication of a special character ​ ​ ​ ​ ​ ​ ​ ​ [st ​ ate ​ ments] the content of subdirectories  ? : Any character, once. ​ ​ ​ ​ ​ ​ ​ ;;  mv /path/ ​ to/file /path/ ​ whe ​ re/ ​ to/move : move esac  * : Any character, 0, 1 or many time. or rename a file or a directory  [...] : Any character that is in the class. ex:  cp /path/ ​ to/file /path/ ​ whe ​ re/ ​ to/copy : copy a function definition [abc], [a-z], [0-9] file  [^...]: Any character that is not in the class. function functionName { ​ ​ ​ -r : copy recurs ​ ively (used to copy directory) ex: [^abc], [^a-z], [^0-9] ​ ​ ​ ​ [st ​ ate ​ ments]  rm /path/ ​ to/file : remove a file  {s1, s2, sN} : match s1 or s2 or sN ​ ​ ​ ​ [return X] ​ ​ ​ -r : remove recurs ​ ively (used to remove } direct ​ ories) control structure (if) ​ ​ ​ -f : force remove condit ​ ional expres ​ sions if <expression>; then  mkdir /path/ ​ dirName : create an empty  && : logical and operator ​ ​ ​ ​ [st ​ ate ​ ments] directory elif <ex ​ pre ​ ssi ​ on>; then  || : logical or operator  rmdir /path/ ​ to/dir : remove a directory (works ​ ​ ​ ​ [st ​ ate ​ ments] only if the direcotry is empty)  [[ string ]] : return 0 if string is not empty else  [[ -z string ]] : return 0 if the string is empty ​ ​ ​ ​ [st ​ ate ​ ments] bash redire ​ ctions  [[ string1 == string2 ]] : return 0 if the string fi  command > file : redirect stdout to file. are equivalent (creates the file if it doesn't exist and overwrite  [[ string1 != string2 ]] : return 0 if the string control structure (while) it if it does exist) are not equivalent  command >> file : redirect stdout to file. while <expression>; do  [[ string =~ pattern ]] : return 0 if the string (creates the file if it doesn't exist and append to ​ ​ ​ ​ [st ​ ate ​ ments] matches the pattern (extended regex) the end it if it does exist) done  [[ -e file ]] : return 0 if the file exists  command 2> file : redirect stderr to file  [[ -d file ]] : return 0 if file is a directory (creates the file if it doesn't exist and overwrite control structure (for)  [[ -f file ]] : return 0 if file is a file it if it does exist) for var in <expression>; do  command 2>> file : redirect stdout to file.  [[ -x file ]] : return 0 if file is executable ​ ​ ​ echo $var (creates the file if it doesn't exist and append to  [[ $n1 -eq $n2 ]] : return 0 if $n1 == $n2 ​ ​ ​ ​ [st ​ ate ​ ments] the end it if it does exist)  [[ $n1 -lt $n2 ]] : return 0 if $n1 < $n2 done  command &> file : redirect stdout and stderr  [[ $n1 -gt $n2 ]] : return 0 if $n1 > $n2 to file (creates the file if it doesn't exist and  [[ $n1 -ge $n2 ]] : return 0 if $n1 >= $n2 overwrite it if it does exist)  [[ $n1 -le $n2 ]] : return 0 if $n1 <= $n2  [[ $n1 -ne $n2 ]] : return 0 if $n1 != $n2 By gregcheater Published 14th March, 2016. Sponsored by Readability-Score.com Last updated 12th April, 2016. cheatography.com/gregcheater/ Measure your website readability! Page 1 of 3. https://readability-score.com

bash Cheat Sheet by gregcheater via cheatography.com/26582/cs/7469/ more basic bash commands more basic bash commands (cont) variables (cont)  passwd : change your password  man comman ​ dName : Display the manual  ${VAR%%pattern} : return a substring of for command comman ​ dName VAR where the longest string (starting from the  history : consult the history of your command end) matching “pattern” will be cut  sudo command : run the command as  jobs : list of your pending proccesses  $? : the exit status of the last command / superuser  cat file1 file2 ... : concat ​ enate files and print function executed. usually 0 when everything  command1 | xargs -i command2 : uses the to stdout went right. output of the command1 as the input of the  more / less file1 file2 .. : diplsay a file page  $# : the number of args passed to the script / command2. output will be accessible via {} in by page on stdout command2 function  tail / head number : display the " ​ num ​ ber ​ " first  $0 : the name of the script or last line of a file on stdout grep (simple regex)  $n : the nth argument passed to the script /  touch file1 file2 ... : change the modifi ​ cation  grep " ​ pat ​ ter ​ n" file1 file2 ... : print the lines function date of the files that matched the pattern  $@ : the list of all the argument passde to  chmod : change the privileges of a file / the script / function ​ ​ ​ -v : print lines that didn't match the pattern directory  Arrays ​ ​ ​ -i : ignore the character case  echo " ​ tex ​ t" : display a line of text to stdout ​ ​ ​ ​ myA ​ rra ​ y=( ​ value1 value2 value3): declare an ​ ​ ​ -l : print the name of the files that have at  sort file1 file2 ... : sort the file (combine files if array least one match many are specified) and print the result to ​ ​ ​ ​ declare -a myArra ​ y=( ​ value1 value2 value3): ​ ​ ​ -o : print only the piece of line that matched stdout (files aren't impacted) declare an array the pattern ​ ​ ​ -r : sort in reverse order ​ ​ ​ ​ ${m ​ yAr ​ ray ​ [in ​ dex]} : access an element ​ ​ ​ -E : uses the extended regex ​ ​ ​ -n : numerical sort (index starts at 0) ​ ​ ​ -q : quiet. returns 0 in $? if at least one line ​ ​ ​ -u : delete duplicated lines ​ ​ ​ ​ myA ​ rra ​ y[i ​ ndex]= : add or modify the element has been matched. 1 if no line matched  wc file1 file2 ... : print to stdout the number of at index charac ​ ters, words and lines of files variables ​ ​ ​ ​ ${# ​ myA ​ rra ​ y[*]} : return the lenght of the array ​ ​ ​ -l : number of lines only  VAR=VARVALUE : create a variable VAR. ​ ​ ​ ​ ${m ​ yAr ​ ray ​ [*]}: all the elements of the array ​ ​ ​ -w : number of words only the variable can be accessed like so: $VAR or ${VAR} simple regex ​ ​ ​ -w : number of characters only  VAR="$VAR2" : $VAR will contains the value  diff file1 file1 : compare file1 and file 2 for  \ : escape character. It deletes the of $VAR2 differ ​ ences signif ​ ication of a special character  VAR='$VAR2' : $VAR will contains $VAR2 ​ ​ ​ -i : ignore the character case  . : joker. It represents any characters  VAR=$(command) : $VAR will contains the ​ ​ ​ -B : ignore empty lines  * : 0, 1 or many repetition of the last output of the command character / sequence of character ​ ​ ​ -w : ignore whites ​ paces  (( VAR = $VAR + 1 )): the double  ^ : The beginning of the line ​ ​ ​ -c : add context to the output (good for parent ​ heses must be used when doing readability)  $ : The end of the line arithm ​ etics  which comman ​ dName : print the path of a  [...] : Any character that is in the class. ex:  ${VAR#pattern} : return a substring of VAR command [abc], [a-z], [0-9] where the smallest string (starting from the  pushd / popd /path/ ​ to/dir : change directory  [^...]: Any character that is not in the class. beginning) matching “pattern” will be cut using the directory stack ex: [^abc], [^a-z], [^0-9]  ${VAR##pattern} : return a substring of VAR  dirs : print the directory stack  \(...\) : Capture the pattern. The pattern can where the longest string (starting from the  find /path/ ​ to/dir -name pattern : find every then be accessed with \1, \2 ... \n depending on beginning) matching “pattern” will be cut the number of capture in the regex files and directory that have a name that  ${VAR%pattern} : return a substring of VAR matches " ​ pat ​ ter ​ n" in the directory specified and  \{n\} : n repeti ​ tions of the last character / where the smallest string (starting from the end) its subdir ​ ect ​ ories sequence of character matching “pattern” will be cut By gregcheater Published 14th March, 2016. Sponsored by Readability-Score.com Last updated 12th April, 2016. cheatography.com/gregcheater/ Measure your website readability! Page 2 of 3. https://readability-score.com