Losing value of variables when exiting while-loop in bash [duplicate] - linux

Question

This question already has answers here:
A variable modified inside a while loop is not remembered
(8 answers)
Closed 4 years ago.
In my script I want to count how many directories and files I have inside different directories. Inside "assignments" I have a lot of directories named "repo1", "repo2" etc. Here is my code:
ls -1 assignments | while read -r repoDir
do
find assignments/"$repoDir" | grep -v .git | grep "$repoDir"/ | while read -r aPathOfRepoDir
do
BASENAME=`basename "$aPathOfRepoDir"`
if [[ -d "$aPathOfRepoDir" ]]; then
totalDirectories=$((totalDirectories+1))
elif [[ -f "$aPathOfRepoDir" ]] && [[ "$BASENAME" == *".txt" ]]; then
totalTextFiles=$((totalTextFiles+1))
else
totalOtherFiles=$((totalOtherFiles+1))
fi
done
echo "total directories: $totalDirectories"
echo "total text files: $totalTextFiles"
echo "total other files: $totalOtherFiles"
totalDirectories=0
totalTextFiles=0
totalOtherFiles=0;
done
When the while-loop is finished I lose the values of those 3 variables. I know that this is happening because the while-loop is a sub-shell but I don't know how can I somehow "store" the values of the variables for the parent shell. I thought about printing those messages inside the while-loop when I know that it's the last "aPathOfRepoDir" but that's kinda a "cheap" way to do it and won't be efficient. Is there another way?
Thanks in advance

Answer 1

Right hand side of a pipe runs in a subshell. Changes in the subshell variables don't propagate to the parent shell. Use process substitution instead:
while read -r aPathOfRepoDir
do
BASENAME=`basename "$aPathOfRepoDir"`
if [[ -d "$aPathOfRepoDir" ]]; then
totalDirectories=$((totalDirectories+1))
elif [[ -f "$aPathOfRepoDir" ]] && [[ "$BASENAME" == *".txt" ]]; then
totalTextFiles=$((totalTextFiles+1))
else
totalOtherFiles=$((totalOtherFiles+1))
fi
done < <(find assignments/"$repoDir" | grep -v .git | grep "$repoDir"/ )

Answer 2

How about this:
classify() {
local -A types=([dir]=0 [txt]=0 [other]=0)
local n=0
while read -r type path; do
if [[ $type == d ]]; then
(( types[dir] ++ ))
elif [[ $type == f && $path == *.txt ]]; then
(( types[txt] ++ ))
else
(( types[other] ++ ))
fi
((n++))
done
if [[ $n -gt 0 ]]; then
echo "$1"
echo "total directories: ${types[dir]}"
echo "total text files: ${types[txt]}"
echo "total other files: ${types[other]}"
fi
}
for repoDir in assignments/*; do
find "$repoDir" \
\( ! -path "$repoDir" -a ! -path '*/.git' -a ! -path '*/.git/*' \) \
-printf '%y %p\n' \
| classify "$repoDir"
done
find can exclude the files you don't want to see
find will also emit the file type to simplify the classification
the "classify" function will loop over the find output to count the various categories.
not parsing ls
the function helps to localize all the variables in a single subshell