Count the number of times a character appears in a string

Question

I need to count the number of times a character repeats itself in a string.

For example: How many times the character / appears in the string down below?

'/file/program-files/test/dev/dev1/Central.pdf.gz'

That one string will be within a variable $v_dir_relatorio.

I need the amount of bars to create a file search logic in directories that the paths vary.

Answer 1

By the way using Perl:

perl -nE 'say tr!/!!' <<< $v_dir_relatorio

The command tr (which turns the character set of the first group into the corresponding of the second) returns the number of characters found.

Answer 2

echo $v_dir_relatorio | grep -o / | wc -l    

1. echo to pass something to the pipeline, in this case $v_dir_relatorio
2. grep to find a pattern, in this case the character '/'. The option -o prints each match found in a row.
3. wc to count. With -l it counts the number of lines, which matches the amount of 'Matches' found.

Answer 3

In shell script (bash) one of the alternatives may be:

echo "/1/2/3/4" | grep -o '/' | wc -l

For your case:

v_dir_relatorio=`echo "$CAMINHO" | grep -o '/' | wc -l`

I found other valid answers on: https://stackoverflow.com/questions/16679369/count-occurrences-of-char-in-string-using-bash

Answer 4

Another alternative is to remove the characters you don’t want by using //[^\/], after that just count the remaining characters:

v_dir_relatorio="'/file/program-files/teste/dev/dev1/Central.pdf.gz"
quantidade="${v_dir_relatorio//[^\/]}"

echo "${#quantidade}"  # 6

See DEMO