How to Print $ in Shell Script

How to print $ in shell script?

You can use:

msg1='$'
ms="${msg1}msg1"
msg2="$ms two"
msg3="$msg2 three"
echo "$msg3"

OUTPUT:

$msg1 two three

PS: Take note of ${msg1} syntax to create variable boundary around msg1. This is used to avoid it making it $msg1msg1

Shell script printing contents of variable containing output of a command removes newline characters

If you want to preserve the newlines, enclose the variable in double quotes:

echo "$stuff"

When you write it without the double quotes, the shell expands $stuff into a space-separated list of words (where 'words' are sequences of non-space characters, and the space characters are blanks and tabs and newlines; upon experimentation, it seems that form feeds, carriage returns and back-spaces are not counted as space).

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Demonstrating interpretation of control characters as white space. ASCII 8 is backspace, 9 is tab, 10 is new line (LF), 11 is vertical tab, 12 is form feed, 13 is carriage return. The first command generates a sequence of characters separated by the various control characters. The second command echoes with the result with the original characters preserved - see the hex dump. The third command echoes the result with the shell splitting the words; you can see that the tab and newline were replaced by blank (0x20).

$ x=$(./ascii 64 65 8 66 67 9 68 69 10 70 71 11 72 73 12 74 75 13 76 77)
$ echo "$x" | odx
0x0000: 40 41 08 42 43 09 44 45 0A 46 47 0B 48 49 0C 4A   @A.BC.DE.FG.HI.J
0x0010: 4B 0D 4C 4D 0A                                    K.LM.
0x0015:
$ echo  $x  | odx
0x0000: 40 41 08 42 43 20 44 45 20 46 47 0B 48 49 0C 4A   @A.BC DE FG.HI.J
0x0010: 4B 0D 4C 4D 0A                                    K.LM.
0x0015:
$ 

Print to screen after setting log file in shell script

Could you please try following. To remove effect of your exec &> file command you can use exec &>/dev/tty to bring writing back to standard output and standard errors. Then we could use tee -a command to write it on screen as well as on file.

cat my_script.sh
log_file="test_file"
exec &> $log_file
echo "12131313113...."
echo "test bla bla bla.."
exec &>/dev/tty
echo "test again...." | tee -a "$log_file"

Now when we run the script the last line should be printed on screen and should be saved into output file too.

./test.sh
test again....
##See the output of test file..
cat test_file
12131313113....
test bla bla bla..
test again....

Or alternatively:
echo "output" > /dev/tty

Print periodic progress messages on the same line

command|awk '{ printf "Progress: %s%%  \r", $1}'

This one is with ProgressBar

command|awk '{printf "\rProgress: " $1 "%% ["; for(c=0;c<$1;c++) printf "#"; printf "]" }'

Progress: 60% [############################################################]

How to print something to the right-most of the console in Linux shell script

Using bash and printf:

printf "%-$(( COLUMNS - ${#errorNumber} ))s%s" \
       "$filePath" "$errorNumber"

How it works:

1. $COLUMNS is the shell's terminal width.

2. printf does left alignment by putting a - after the %. So printf "%-25s%s\n" foo bar prints "foo", then 22 spaces, then "bar".

3. bash uses the # as a parameter length variable prefix, so if x=foo, then ${#x} is 3.

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Fancy version, suppose the two variables are longer than will fit in one column; if so print them on as many lines as are needed:

printf "%-$(( COLUMNS * ( 1 + ( ${#filePath} + ${#errorNumber} ) / COLUMNS ) \
          - ${#errorNumber} ))s%s"   "$filePath" "$errorNumber"

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Generalized to a function. Syntax is printfLR foo bar, or printfLR < file:

printfLR() { if [ "$1" ] ; then echo "$@" ; else cat ; fi |
             while read l r ; do
                 printf "%-$(( ( 1 + ( ${#l} + ${#r} ) / COLUMNS ) \
                              * COLUMNS - ${#r} ))s%s"   "$l" "$r"
             done ;  }

Test with:

# command line args
printfLR foo bar
# stdin
fortune | tr -s ' \t' '\n\n' | paste - - | printfLR

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