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readarray -t arr <file Or with a loop: arr=() while IFS= read -r line; do arr+=("$line") done <file

while IFS= read -r line; do echo "$line" done <file If file may not include a newline at the end, then: while IFS= read -r line || [ -n "$line" ]; do echo "$line" done <file

var='line 1 line 2 line3' readarray -t arr <<< "$var" or with a loop: arr=() while IFS= read -r line; do arr+=("$line") done <<< "$var"

var='line 1 line 2 line3' while IFS= read -r line; do echo "-$line-" done <<< "$var" or readarray -t arr <<< "$var" for i in "${arr[@]}";do echo "-$i-" done

while IFS= read -r line;do echo "**$line**" done < <(ping google.com) or with a pipe: ping google.com | while IFS= read -r line;do echo "**$line**" done

Let's assume that the field separator is : (colon) in the file file. while IFS= read -d : -r field || [ -n "$field" ]; do echo "$field" done <file For a content: first : se con d: Thi rd: Fourth The output is: **first ** ** se con d** ** Thi ...

The NSString formatting supports all the format strings available on the printf ANSI-C function. The only addition made by the language is the %@ symbol used for formatting all the Objective-C objects. It is possible to format integers int myAge = 21; NSString *formattedAge = [NSString stringWith...

Let's assume that the field separator is : var='line: 1 line: 2 line3' while IFS= read -d : -r field || [ -n "$field" ]; do echo "-$field-" done <<< "$var" Output: -line- - 1 line- - 2 line3 -

Let's assume that the field separator is : arr=() while IFS= read -d : -r field || [ -n "$field" ]; do arr+=("$field") done <file

Let's assume that the field separator is : var='1:2:3:4: newline' arr=() while IFS= read -d : -r field || [ -n "$field" ]; do arr+=("$field") done <<< "$var" echo "${arr[4]}" Output: newline

Let's assume that the field separator is : while IFS= read -d : -r field || [ -n "$field" ];do echo "**$field**" done < <(ping google.com) Or with a pipe: ping google.com | while IFS= read -d : -r field || [ -n "$field" ];do echo "**$field**&q...

pat='[^0-9]+([0-9]+)' s='I am a string with some digits 1024' [[ $s =~ $pat ]] # $pat must be unquoted echo "${BASH_REMATCH[0]}" echo "${BASH_REMATCH[1]}" Output: I am a string with some digits 1024 1024 Instead of assigning the regex to a variable ($pat) we could als...

A simple example which provides the options: OptAlt. OptDetails-h--helpShow help-v--versionShow version info-dr path--doc-root pathAn option which takes a secondary parameter (a path)-i--installA boolean option (true/false)-*--Invalid option #!/bin/bash dr='' install=false skip=false for op ...

a='I am a simple string with digits 1234' pat='(.*) ([0-9]+)' [[ "$a" =~ $pat ]] echo "${BASH_REMATCH[0]}" echo "${BASH_REMATCH[1]}" echo "${BASH_REMATCH[2]}" Output: I am a simple string with digits 1234 I am a simple string with digits 1234

This counts the number of lines in a big file with wc -l while simultaneously compressing it with gzip. Both run concurrently. tee >(wc -l >&2) < bigfile | gzip > bigfile.gz Normally tee writes its input to one or more files (and stdout). We can write to commands instead of fil...

The following function reads an entire file into a new string and returns it: (defun read-file (infile) (with-open-file (instream infile :direction :input :if-does-not-exist nil) (when instream (let ((string (make-string (file-length instream)))) (read-sequence string instr...

Class Car ... ' Parameterless Constructor Public Sub Class_Initialize() distances_ = Array(0) End Sub ' Default initialization method that can be invoked without ' explicitly using the method name. Public Default Function Init(wheels) wheels_ = ...

Quotes will be output as-is: echo "Some Text" "Some Text" Comment tokens are ignored: echo Hello World REM this is not a comment because it is being echoed! Hello World REM this is not a comment because it is being echoed! However, echo will still output var...

SET TEST=0 IF %TEST% == 0 ( echo TEST FAILED ) ELSE IF %TEST% == 1 ( echo TEST PASSED ) ELSE ( echo TEST INVALID )

FIND command can scan large files line-by-line to find a certain string. It doesn't support wildcards in the search string. find /i "Completed" "%userprofile%\Downloads\*.log" >> %targetdir%\tested.log TYPE scan2.txt | FIND "Failed" /c && echo Scan fai...