Bash shell script doesn't create subfolders

Question

I have a bash shell script as follows.

#!/bin/bash
MKDIR(){
    if [ ! -d $1 ]; then
        mkdir -p $1
    fi
}
WORKER_CNT=4
dirs=/home/sysadmin/Nyan/cv_samples_v1.3.0/action_recognition_net/data/selfinf
declare -a RGB_PATH_LIST
i=0
for entry in "$dirs"/*
do
  RGB_PATH_LIST[i++]="$entry"
done

#for((i=1;i<=${#RGB_PATH_LIST[@]};i++))
#do
#    echo "${RGB_PATH_LIST[i]}"
#done

RUN_WORKERS(){
    echo "$RGB_PATH_LIST"
    for((i=0;i<$RGB_PATH_LIST;i++)); do
        if [ ${RGB_PATH_LIST[i]} != "NULL" ]; then
            mkdir -p ${RGB_PATH_LIST[i]}/"flow"
            mkdir -p ${RGB_PATH_LIST[i]}/"of"
            ./AppOFCuda --input=${RGB_PATH_LIST[i]}/"rgb"/"*.png" --output=${RGB_PATH_LIST[i]}/"flow" --preset=fast --gridSize=1 \
            &&
            python ./convert_of.py --input_flow_folder ${RGB_PATH_LIST[i]}/"flow" --output_folder ${RGB_PATH_LIST[i]}/"of" &
        fi
    done
    wait
     for((i=0;i<$WORKER_CNT;i++)); do
         if [ ${RGB_PATH_LIST[i]} != "NULL" ]; then
             rm -r ${RGB_PATH_LIST[i]}/"flow"
         fi
     done
}

But it doesn't create any flow and of subfolders inside RGB_PATH_LIST folders. How can I solve?

If `mkdir` does not print an error message, I guess the directories are created at a different place than you think. Do a `ls -ld ${RGB_PATH_LIST[i]}/*` after the mkdir and check.... — user1934428, Aug 15 '23 at 07:29
I don't see anything that actually runs either function. Also, in `for((i=0;i<$RGB_PATH_LIST;i++))` you probably want `${RGB_PATH_LIST[@]}` (the number of elements in the array, not the first element), and I don't see how any element could ever be "NULL". [shellcheck.net](https://www.shellcheck.net) will point out a bunch of other problems/bad practices, especially bad quoting (e.g. use `"${RGB_PATH_LIST[i]}/flow"` instead of `${RGB_PATH_LIST[i]}/"flow"`). — Gordon Davisson, Aug 15 '23 at 07:41
`mkdir -p $1` should be replaced by `mkdir -p "$1"` (with quotes) to accept directory names with special characters. — Wiimm, Aug 15 '23 at 12:36
shorter version of `if [ ! -d $1 ]; then mkdir -p "$1"; fi` is `[ -d "$1" ] || mkdir -p "$1"`. But `mkdir -p` includes the condition, a simple `mkdir -p "$1"` does the same. — Wiimm, Aug 15 '23 at 12:39
I really wish the SO folks would make the [tag:bash] tag instruction mandatory - "For shell scripts with syntax or other errors, please check them at https://shellcheck.net before posting them here.". See also [correct-bash-and-shell-script-variable-capitalization](https://stackoverflow.com/questions/673055/correct-bash-and-shell-script-variable-capitalization) — Ed Morton, Aug 15 '23 at 20:25

score 1 · Accepted Answer · answered Aug 15 '23 at 07:41

the for loop is not iterating correctly over the RGB_PATH_LIST array and you must to edit the line for((i=0;i<$RGB_PATH_LIST;i++)); do to for((i=0;i<${#RGB_PATH_LIST[@]};i++)); do

check it out :

#!/bin/bash
MKDIR(){
    if [ ! -d $1 ]; then
        mkdir -p $1
    fi
}
WORKER_CNT=4
dirs=/home/sysadmin/Nyan/cv_samples_v1.3.0/action_recognition_net/data/selfinf
declare -a RGB_PATH_LIST
i=0
for entry in "$dirs"/*
do
  RGB_PATH_LIST[i++]="$entry"
done

#for((i=1;i<=${#RGB_PATH_LIST[@]};i++))
#do
#    echo "${RGB_PATH_LIST[i]}"
#done

RUN_WORKERS(){
    echo "$RGB_PATH_LIST"
    for((i=0;i<${#RGB_PATH_LIST[@]};i++)); do
        if [ ${RGB_PATH_LIST[i]} != "NULL" ]; then
            mkdir -p ${RGB_PATH_LIST[i]}/"flow"
            mkdir -p ${RGB_PATH_LIST[i]}/"of"
            ./AppOFCuda --input=${RGB_PATH_LIST[i]}/"rgb"/"*.png" --output=${RGB_PATH_LIST[i]}/"flow" --preset=fast --gridSize=1 \
            &&
            python ./convert_of.py --input_flow_folder ${RGB_PATH_LIST[i]}/"flow" --output_folder ${RGB_PATH_LIST[i]}/"of" &
        fi
    done
    wait
     for((i=0;i<$WORKER_CNT;i++)); do
         if [ ${RGB_PATH_LIST[i]} != "NULL" ]; then
             rm -r ${RGB_PATH_LIST[i]}/"flow"
         fi
     done
}

RUN_WORKERS

I don't have access right now to check, but it seems to me that this method should solve the problem. Please let me know the result. thnx.

Bash shell script doesn't create subfolders

1 Answers1