multiple conditions on 'if'

Question

I'm trying to write a bash script that loops over directories that start with one of two strings in a given folder. I wrote the following:

for aSubj in /wherever/*
    if [ [ -d $aSubj ] && [ [ $aSubj == hu* ] || [ $aSubj == ny* ] ] ]; then
        .
        .
    fi
done

When I try and run this I get a syntax error on the line of the 'if': syntax error near unexpected token 'if'

Can anyone point out where I'm going wrong?

each condition has just one '[', but some of them are nested — Henry Brice, Oct 21 '15 at 16:51
Right, but `[` doesn't nest that way. `[` is actually a command, nearly equivalent to the `test` command, and it doesn't recognize a `[` in its arguments. — Keith Thompson, Oct 21 '15 at 18:34

score 1 · Accepted Answer · answered Oct 21 '15 at 16:19

1

The 1st line should be

for aSubj in /wherever/*; do

answered Oct 21 '15 at 16:19

timrau

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I have another question - the variable aSubj is ending up as the entire file path (that is, /wherever/aSubj ). How can I get the variable to be just the directory name? – Henry Brice Oct 21 '15 at 16:38

score 1 · Answer 2 · edited May 23 '17 at 10:27

If you want to mention multiple conditions, just nest them with ( ):

$ d=23
$ ( [ $d -ge 20 ] && [ $d -ge 5 ] ) || [ $d -ge 5 ] && echo "yes"
yes

However, in this case you may want to use a regular expression as described in Check if a string matches a regex in Bash script:

[[ $aSubj =~ ^(hu|ny)* ]]

This checks if the content in the variable $aSubj starts with either hu or ny.

Or even use the regular expression to fetch the files. For example, the following will match all files in ttt/ directory whose name starts by either a or b:

for file in ttt/[ab]*

Note you can also feed your loop with using a process substitution with find containing a regular expression (samples in How to use regex in file find):

while IFS= read -r file
do
   # .... things
done < <(find your_dir -mindepth 1 -maxdepth 1 -type d -regex '.*/\(hu\|ny\).*')

For example, if I have the following dirs:

$ ls dirs/
aa23  aa24  ba24  bc23  ca24

I get this result if I look for directories whose name starts by either ca or bc:

$ find dirs -mindepth 1 -maxdepth 1 -type d -regex '.*/\(ca\|bc\).*'
dirs/bc23
dirs/ca24

multiple conditions on 'if'

2 Answers2