How to properly use command substitution in a select loop - bash

The purpose of the script is to act as a directory navigator. Currently, I''m trying to print all the directories within the current directory using the fourth arguement in the select loop. I understand that I need to use command substitution but do not understand how to properly implement the backticks.
#! /bin/bash
echo"###################################################################"
pwd | ls -l
#problem with bad substitution below inbetween backticks
select choice in quit back jump ${`ls -l | egrep '^d' | awk $9`};
do
case $choice in
"quit")
echo "Quitting program"
exit 0
break
;;
"back")
cd ..
echo "Your have gone back to the previous directory: " `pwd`
pwd
ls -l
;;
"jump")
echo "Enter the directory you want to move into"
read inputDir
if [[ -d $inputdir ]]; then
cd $inputDir
pwd
ls -l
else
echo "Your input is not a directory, Please enter correct Di$
fi
;;
${ls -l | egrep '^d' | awk $9})
esac
done

You should really look at using shellcheck to lint your shell scripts.
I use mapfile to create an array based on output. I also use find instead ls of because it handles non-alphanumeric filenames better.
I then create an array with the output appended. There are different ways to do it, but this is most straight-forward. More information about bash arrays here.
#! /bin/bash
echo"###############################################################"
pwd # Your script had a |, it doesn't do anything since ls -l, doesn't take
# input from stdin. I seperated them, because that's probably what you want
ls -l
mapfile -t output < <(find . -type d -maxdepth 1 -not -name '.*' | sed -e 's/^\.\///')
choices=(quit back jump "${output[#]}")
select choice in "${choices[#]}"; do
case $choice in
"quit")
echo "Quitting program"
exit 0
break
;;
"back")
cd ..
echo "Your have gone back to the previous directory: $(pwd)"
pwd
ls -l
;;
"jump")
echo "Enter the directory you want to move into"
read -r inputDir
if [[ -d $inputDir ]]; then
cd "$inputDir" || exit
pwd
ls -l
else
echo "Your input is not a directory, Please enter correct Di$"
fi
;;
esac
done

Related

why 'ls' command printing the directory content multiple times

I have the following shell script in which I want to check the specific directory content on the remote machines and print them in a file.
file=serverList.csv
n=0
while [ $n -le 2 ]
do
while IFS=: read -r f1 f2
do
# echo line is stored in $line
if echo $f1 | grep -q "xx.xx.xxx";
then
ssh user#$f1 ls path/*war_* > path/$f1.txt < /dev/null; ls path/*zip_* >> path/$f1.txt < /dev/null;
ssh user#$f1 ls -d /apps/jetty*_* >> path/$f1.txt < /dev/null;
fi
done < "$file"
sleep 15
n=$(( n+1 ))
done
I am using this script inside a cron job for every 2 minute as following:
*/2 * * * * /path/myscript.sh
but somehow I am ending up with the following output file:
/apps/jetty/webapps_wars/test_new.war
path/ReleaseTest.static.zip_2020-08-05
path/ReleaseTest.static.zip_2020-08-05
path/ReleaseTest.static.zip_2020-08-05
path/jetty_xx.xx_2020-08-05
path/jetty_new
path/jetty_xx.xx_2020-08-05
path/jetty_new
I am not sure why am I getting the files in the list twice, sometimes 3 times. but I execute the shell directly from putty, it works fine. What do I need to change in order to correct this script?
Example:
~$ cd tmp
~/tmp$ mkdir test
~/tmp$ cd !$
cd test
~/tmp/test$ mkdir -p apps/jetty/webapp_wars/ && touch apps/jetty/webapp_wars/test_new.war
~/tmp/test$ mkdir path
~/tmp/test$ touch path/{ReleaseTest.static.zip_2020-08-05,jetty_xx.xx_2020-08-05,jetty_new}
~/tmp/test$ cd ..
~/tmp$ listpath=$(find test/path \( -name "*2020-08-05" -o -name "*new" \) )
~/tmp$ listapps=$(find test/apps/ -name "*war" )
~/tmp$ echo ${listpath[#]}" "${listapps[#]} | tr " " "\n" | sort > resultfile
~/tmp$
~/tmp$ cat resultfile
test/apps/jetty/webapp_wars/test_new.war
test/path/jetty_new
test/path/jetty_xx.xx_2020-08-05
test/path/ReleaseTest.static.zip_2020-08-05
~/tmp$ rm -rf test/ && unset listapps && unset listpath && rm resultfile
~/tmp$
This way you get only one result for each pattern you are looking for in your if...then...else block of code.
Just adapt the ssh ..... find commands and take care of quotes & parentheses but there is the easiest solution, this way you do not have to rewrite the script from scratch. And be careful on local / remote variables if you use them.
You really should not use ls but the fundamental problem is probably that three separate commands with three separate wildcards could match the same file three times.
Also, one of your commands is executed locally (you forgot to put ssh etc in front of the second one), so if the wildcard matches on your local computer, that would produce a result which doesn't reflect the situation on the remote server.
Try this refactoring.
file=serverList.csv
n=0
while [ $n -le 2 ]
do
while IFS=: read -r f1 f2
do
# echo line is stored in $line <- XXX this is not true
if echo "$f1" | grep -q "xx.xx.xxx";
then
ssh user#$f1 "printf '%s\n' path/*war_* path/*zip_* /apps/jetty*_*" | sort -u >path/"$f1".txt < /dev/null
fi
done < "$file"
sleep 15
n=$(( n+1 ))
done
The sort gets rid of any duplicates. This assumes none of your file names contain newlines; if they do, you'd need to use something which robustly handles them (try printf '%s\0' and sort -z but these are not portable).
ls would definitely also accept three different wildcards but like the link above explains, you really never want to use ls in scripts.

bash call script with variable

What I want to achieve is the following :
I want the subtitles for my TV Show downloaded automatically.
The script "getSubtitle.sh" is ran as soon as the show is downloaded, but it can happen that no subtitle are released yet.
So what I am doing to counter this :
Creating a file each time "getSubtitle.sh" is ran. It contain the location of the script with its arguments, for example :
/Users/theo/logSubtitle/getSubtitle.sh "The Walking Dead - 5x10 - Them.mp4" "The.Walking.Dead.S05E10.480p.HDTV.H264.mp4" "/Volumes/Window HD/Série/The Walking Dead"
If a subtitle has been found, this file will contain only this line, if no subtitle has been found, this file will have 2 lines (the first one being "no subtitle downloaded", and the second one being the path to the script as explained above)
Now, once I get this, I'm planning to run a cron everyday that will do the following :
Remove all file that have only 1 line (Subtitle found), and execute the script again for the remaining file. Here is the full script :
cd ~/logSubtitle/waiting/
for f in *
do nbligne=$(wc -l $f | cut -c 8)
if [ "$nbligne" = "1" ]
then
rm $f
else
command=$(sed -n "2 p" $f)
sh $command 3>&1 1>&2 2>&3 | grep down > $f ; echo $command >> $f
fi
done
This is unfortunately not working, I have the feeling that the script is not called.
When I replace $command by the line in the text file, it is working.
I am sure that $command match the line because of the "echo $command >> $f" at the end of my script.
So I really don't get what I am missing here, any ideas ?
Thanks.
I'm not sure what you're trying to achieve with the cut -c 8 part in wc -l $f | cut -c 8. cut -c 8 will select the 8th character of the output of wc -l.
A suggestion: to check whether your file contains 1 or two lines (and since you'll need the content of the second line, if any, anyway), use mapfile. This will slurp the file in an array, one line per field. You can use the option -n 2 to read at most 2 lines. This will be much more efficient, safe and nice than your solution:
mapfile -t -n 2 ary < file
Then:
if ((${#ary[#]}==1)); then
printf 'File contains one line only: %s\n' "${ary[0]}"
elif ((${#ary[#]==2)); then
printf 'File contains (at least) two lines:\n'
printf ' %s\n' "${ary[#]}"
else
printf >&2 'Error, no lines found in file\n'
fi
Another suggestion: use more quotes!
With this, a better way to write your script:
#!/bin/bash
dir=$HOME/logSubtitle/waiting/
shopt -s nullglob
for f in "$dir"/*; do
mapfile -t -n 2 ary < "$f"
if ((${#ary[#]}==1)); then
rm -- "$f" || printf >&2 "Error, can't remove file %s\n" "$f"
elif ((${#ary[#]}==2)); then
{ sh -c "${ary[1]}" 3>&1 1>&2 2>&3 | grep down; echo "${ary[1]}"; } > "$f"
else
printf >&2 'Error, file %s contains no lines\n' "$f"
fi
done
After the done keyword you can even add the redirection 2>> logfile to a log file if you wish. Make sure the cron job is run with your user: check crontab -l and, if needed, edit it with crontab -e.
Use eval instead of sh. The reason it works with eval and not sh is due to the number of passes to evaluate variables. sh will treat the sed command as its command to execute while eval will evaluate the sed command first and then execute the result.
Briefly explained.

How to find latest modified files and delete them with SHELL code

I need some help with a shell code. Now I have this code:
find $dirname -type f -exec md5sum '{}' ';' | sort | uniq --all-repeated=separate -w 33 | cut -c 35-
This code finds duplicated files (with same content) in a given directory. What I need to do is to update it - find out latest (by date) modified file (from duplicated files list), print that file name and also give opportunity to delete that file in terminal.
Doing this in pure bash is a tad awkward, it would be a lot easier to write
this in perl or python.
Also, if you were looking to do this with a bash one-liner, it might be feasible,
but I really don't know how.
Anyhoo, if you really want a pure bash solution below is an attempt at doing
what you describe.
Please note that:
I am not actually calling rm, just echoing it - don't want to destroy your files
There's a "read -u 1" in there that I'm not entirely happy with.
Here's the code:
#!/bin/bash
buffer=''
function process {
if test -n "$buffer"
then
nbFiles=$(printf "%s" "$buffer" | wc -l)
echo "================================================================================="
echo "The following $nbFiles files are byte identical and sorted from oldest to newest:"
ls -lt -c -r $buffer
lastFile=$(ls -lt -c -r $buffer | tail -1)
echo
while true
do
read -u 1 -p "Do you wish to delete the last file $lastFile (y/n/q)? " answer
case $answer in
[Yy]* ) echo rm $lastFile; break;;
[Nn]* ) echo skipping; break;;
[Qq]* ) exit;;
* ) echo "please answer yes, no or quit";;
esac
done
echo
fi
}
find . -type f -exec md5sum '{}' ';' |
sort |
uniq --all-repeated=separate -w 33 |
cut -c 35- |
while read -r line
do
if test -z "$line"
then
process
buffer=''
else
buffer=$(printf "%s\n%s" "$buffer" "$line")
fi
done
process
echo "done"
Here's a "naive" solution implemented in bash (except for two external commands: md5sum, of course, and stat used only for user's comfort, it's not part of the algorithm). The thing implements a 100% Bash quicksort (that I'm kind of proud of):
#!/bin/bash
# Finds similar (based on md5sum) files (recursively) in given
# directory. If several files with same md5sum are found, sort
# them by modified (most recent first) and prompt user for deletion
# of the oldest
die() {
printf >&2 '%s\n' "$#"
exit 1
}
quicksort_files_by_mod_date() {
if ((!$#)); then
qs_ret=()
return
fi
# the return array is qs_ret
local first=$1
shift
local newers=()
local olders=()
qs_ret=()
for i in "$#"; do
if [[ $i -nt $first ]]; then
newers+=( "$i" )
else
olders+=( "$i" )
fi
done
quicksort_files_by_mod_date "${newers[#]}"
newers=( "${qs_ret[#]}" )
quicksort_files_by_mod_date "${olders[#]}"
olders=( "${qs_ret[#]}" )
qs_ret=( "${newers[#]}" "$first" "${olders[#]}" )
}
[[ -n $1 ]] || die "Must give an argument"
[[ -d $1 ]] || die "Argument must be a directory"
dirname=$1
shopt -s nullglob
shopt -s globstar
declare -A files
declare -A hashes
for file in "$dirname"/**; do
[[ -f $file ]] || continue
read md5sum _ < <(md5sum -- "$file")
files[$file]=$md5sum
((hashes[$md5sum]+=1))
done
has_found=0
for hash in "${!hashes[#]}"; do
((hashes[$hash]>1)) || continue
files_with_same_md5sum=()
for file in "${!files[#]}"; do
[[ ${files[$file]} = $hash ]] || continue
files_with_same_md5sum+=( "$file" )
done
has_found=1
echo "Found ${hashes[$hash]} files with md5sum=$hash, sorted by modified (most recent first):"
# sort them by modified date (using quicksort :p)
quicksort_files_by_mod_date "${files_with_same_md5sum[#]}"
for file in "${qs_ret[#]}"; do
printf " %s %s\n" "$(stat --printf '%y' -- "$file")" "$file"
done
read -p "Do you want to remove the oldest? [yn] " answer
if [[ ${answer,,} = y ]]; then
echo rm -fv -- "${qs_ret[#]:1}"
fi
done
if((!has_found)); then
echo "Didn't find any similar files in directory \`$dirname'. Yay."
fi
I guess the script is self-explanatory (you can read it like a story). It uses the best practices I know of, and is 100% safe regarding any silly characters in file names (e.g., spaces, newlines, file names starting with hyphens, file names ending with a newline, etc.).
It uses bash's globs, so it might be a bit slow if you have a bloated directory tree.
There are a few error checkings, but many are missing, so don't use as-is in production! (it's a trivial but rather tedious taks to add these).
The algorithm is as follows: scan each file in the given directory tree; for each file, will compute its md5sum and store in associative arrays:
files with keys the file names and values the md5sums.
hashes with keys the hashes and values the number of files the md5sum of which is the key.
After this is done, we'll scan through all the found md5sum, select only the ones that correspond to more than one file, then select all files with this md5sum, then quicksort them by modified date, and prompt the user.
A sweet effect when no dups are found: the script nicely informs the user about it.
I would not say it's the most efficient way of doing things (might be better in, e.g., Perl), but it's really a lot of fun, surprisingly easy to read and follow, and you can potentially learn a lot by studying it!
It uses a few bashisms and features that only are in bash version ≥ 4
Hope this helps!
Remark. If on your system date has the -r switch, you can replace the stat command by:
date -r "$file"
Remark. I left the echo in front of rm. Remove it if you're happy with how the script behaves. Then you'll have a script that uses 3 external commands :).

Test if a command outputs an empty string

How can I test if a command outputs an empty string?
Previously, the question asked how to check whether there are files in a directory. The following code achieves that, but see rsp's answer for a better solution.
Empty output
Commands don’t return values – they output them. You can capture this output by using command substitution; e.g. $(ls -A). You can test for a non-empty string in Bash like this:
if [[ $(ls -A) ]]; then
echo "there are files"
else
echo "no files found"
fi
Note that I've used -A rather than -a, since it omits the symbolic current (.) and parent (..) directory entries.
Note: As pointed out in the comments, command substitution doesn't capture trailing newlines. Therefore, if the command outputs only newlines, the substitution will capture nothing and the test will return false. While very unlikely, this is possible in the above example, since a single newline is a valid filename! More information in this answer.
Exit code
If you want to check that the command completed successfully, you can inspect $?, which contains the exit code of the last command (zero for success, non-zero for failure). For example:
files=$(ls -A)
if [[ $? != 0 ]]; then
echo "Command failed."
elif [[ $files ]]; then
echo "Files found."
else
echo "No files found."
fi
More info here.
TL;DR
if [[ $(ls -A | head -c1 | wc -c) -ne 0 ]]; then ...; fi
Thanks to netj
for a suggestion to improve my original:if [[ $(ls -A | wc -c) -ne 0 ]]; then ...; fi
This is an old question but I see at least two things that need some improvement or at least some clarification.
First problem
First problem I see is that most of the examples provided here simply don't work. They use the ls -al and ls -Al commands - both of which output non-empty strings in empty directories. Those examples always report that there are files even when there are none.
For that reason you should use just ls -A - Why would anyone want to use the -l switch which means "use a long listing format" when all you want is test if there is any output or not, anyway?
So most of the answers here are simply incorrect.
Second problem
The second problem is that while some answers work fine (those that don't use ls -al or ls -Al but ls -A instead) they all do something like this:
run a command
buffer its entire output in RAM
convert the output into a huge single-line string
compare that string to an empty string
What I would suggest doing instead would be:
run a command
count the characters in its output without storing them
or even better - count the number of maximally 1 character using head -c1(thanks to netj for posting this idea in the comments below)
compare that number with zero
So for example, instead of:
if [[ $(ls -A) ]]
I would use:
if [[ $(ls -A | wc -c) -ne 0 ]]
# or:
if [[ $(ls -A | head -c1 | wc -c) -ne 0 ]]
Instead of:
if [ -z "$(ls -lA)" ]
I would use:
if [ $(ls -lA | wc -c) -eq 0 ]
# or:
if [ $(ls -lA | head -c1 | wc -c) -eq 0 ]
and so on.
For small outputs it may not be a problem but for larger outputs the difference may be significant:
$ time [ -z "$(seq 1 10000000)" ]
real 0m2.703s
user 0m2.485s
sys 0m0.347s
Compare it with:
$ time [ $(seq 1 10000000 | wc -c) -eq 0 ]
real 0m0.128s
user 0m0.081s
sys 0m0.105s
And even better:
$ time [ $(seq 1 10000000 | head -c1 | wc -c) -eq 0 ]
real 0m0.004s
user 0m0.000s
sys 0m0.007s
Full example
Updated example from the answer by Will Vousden:
if [[ $(ls -A | wc -c) -ne 0 ]]; then
echo "there are files"
else
echo "no files found"
fi
Updated again after suggestions by netj:
if [[ $(ls -A | head -c1 | wc -c) -ne 0 ]]; then
echo "there are files"
else
echo "no files found"
fi
Additional update by jakeonfire:
grep will exit with a failure if there is no match. We can take advantage of this to simplify the syntax slightly:
if ls -A | head -c1 | grep -E '.'; then
echo "there are files"
fi
if ! ls -A | head -c1 | grep -E '.'; then
echo "no files found"
fi
Discarding whitespace
If the command that you're testing could output some whitespace that you want to treat as an empty string, then instead of:
| wc -c
you could use:
| tr -d ' \n\r\t ' | wc -c
or with head -c1:
| tr -d ' \n\r\t ' | head -c1 | wc -c
or something like that.
Summary
First, use a command that works.
Second, avoid unnecessary storing in RAM and processing of potentially huge data.
The answer didn't specify that the output is always small so a possibility of large output needs to be considered as well.
if [ -z "$(ls -lA)" ]; then
echo "no files found"
else
echo "There are files"
fi
This will run the command and check whether the returned output (string) has a zero length.
You might want to check the 'test' manual pages for other flags.
Use the "" around the argument that is being checked, otherwise empty results will result in a syntax error as there is no second argument (to check) given!
Note: that ls -la always returns . and .. so using that will not work, see ls manual pages. Furthermore, while this might seem convenient and easy, I suppose it will break easily. Writing a small script/application that returns 0 or 1 depending on the result is much more reliable!
For those who want an elegant, bash version-independent solution (in fact should work in other modern shells) and those who love to use one-liners for quick tasks. Here we go!
ls | grep . && echo 'files found' || echo 'files not found'
(note as one of the comments mentioned, ls -al and in fact, just -l and -a will all return something, so in my answer I use simple ls
Bash Reference Manual
6.4 Bash Conditional Expressions
-z string
True if the length of string is zero.
-n string
string
True if the length of string is non-zero.
You can use shorthand version:
if [[ $(ls -A) ]]; then
echo "there are files"
else
echo "no files found"
fi
As Jon Lin commented, ls -al will always output (for . and ..). You want ls -Al to avoid these two directories.
You could for example put the output of the command into a shell variable:
v=$(ls -Al)
An older, non-nestable, notation is
v=`ls -Al`
but I prefer the nestable notation $( ... )
The you can test if that variable is non empty
if [ -n "$v" ]; then
echo there are files
else
echo no files
fi
And you could combine both as if [ -n "$(ls -Al)" ]; then
Sometimes, ls may be some shell alias. You might prefer to use $(/bin/ls -Al). See ls(1) and hier(7) and environ(7) and your ~/.bashrc (if your shell is GNU bash; my interactive shell is zsh, defined in /etc/passwd - see passwd(5) and chsh(1)).
I'm guessing you want the output of the ls -al command, so in bash, you'd have something like:
LS=`ls -la`
if [ -n "$LS" ]; then
echo "there are files"
else
echo "no files found"
fi
sometimes "something" may come not to stdout but to the stderr of the testing application, so here is the fix working more universal way:
if [[ $(partprobe ${1} 2>&1 | wc -c) -ne 0 ]]; then
echo "require fixing GPT parititioning"
else
echo "no GPT fix necessary"
fi
Here's a solution for more extreme cases:
if [ `command | head -c1 | wc -c` -gt 0 ]; then ...; fi
This will work
for all Bourne shells;
if the command output is all zeroes;
efficiently regardless of output size;
however,
the command or its subprocesses will be killed once anything is output.
All the answers given so far deal with commands that terminate and output a non-empty string.
Most are broken in the following senses:
They don't deal properly with commands outputting only newlines;
starting from Bash≥4.4 most will spam standard error if the command output null bytes (as they use command substitution);
most will slurp the full output stream, so will wait until the command terminates before answering. Some commands never terminate (try, e.g., yes).
So to fix all these issues, and to answer the following question efficiently,
How can I test if a command outputs an empty string?
you can use:
if read -n1 -d '' < <(command_here); then
echo "Command outputs something"
else
echo "Command doesn't output anything"
fi
You may also add some timeout so as to test whether a command outputs a non-empty string within a given time, using read's -t option. E.g., for a 2.5 seconds timeout:
if read -t2.5 -n1 -d '' < <(command_here); then
echo "Command outputs something"
else
echo "Command doesn't output anything"
fi
Remark. If you think you need to determine whether a command outputs a non-empty string, you very likely have an XY problem.
Here's an alternative approach that writes the std-out and std-err of some command a temporary file, and then checks to see if that file is empty. A benefit of this approach is that it captures both outputs, and does not use sub-shells or pipes. These latter aspects are important because they can interfere with trapping bash exit handling (e.g. here)
tmpfile=$(mktemp)
some-command &> "$tmpfile"
if [[ $? != 0 ]]; then
echo "Command failed"
elif [[ -s "$tmpfile" ]]; then
echo "Command generated output"
else
echo "Command has no output"
fi
rm -f "$tmpfile"
Sometimes you want to save the output, if it's non-empty, to pass it to another command. If so, you could use something like
list=`grep -l "MY_DESIRED_STRING" *.log `
if [ $? -eq 0 ]
then
/bin/rm $list
fi
This way, the rm command won't hang if the list is empty.
As mentioned by tripleee in the question comments , use moreutils ifne (if input not empty).
In this case we want ifne -n which negates the test:
ls -A /tmp/empty | ifne -n command-to-run-if-empty-input
The advantage of this over many of the another answers when the output of the initial command is non-empty. ifne will start writing it to STDOUT straight away, rather than buffering the entire output then writing it later, which is important if the initial output is slowly generated or extremely long and would overflow the maximum length of a shell variable.
There are a few utils in moreutils that arguably should be in coreutils -- they're worth checking out if you spend a lot of time living in a shell.
In particular interest to the OP may be dirempty/exists tool which at the time of writing is still under consideration, and has been for some time (it could probably use a bump).

make alias for ls so that it doesn't show files of the pattern *~

Is there a series of commands that does ls then removes backup files? I want to do something like
ls | grep -v *~
but this shows all the files in different lines, any one to make the output identical to ls?
When I type in "man ls" My man page for ls has this option of -B its
-B Force printing of non-printable characters (as defined by ctype(3)
and current locale settings) in file names as \xxx, where xxx is the
numeric value of the character in octal.
It is not identical to the one you showed and I searched for ignored but no results popped up. Btw I am on a mac, which might have a different version of ls?
Alternatively, can I tell a directory to stop making backup files?
Assuming ls from GNU coreutils,
-B, --ignore-backups
do not list implied entries ending with ~
You can also set FIGNORE='~' in Bash so that * never expands to contain filenames ending in ~.
You can list all files ending in ~ with:
ls -d *[^~]
The *[^~] specifies all files that don't end in ~. The -d flag tells ls not to show the directory contents for any directories that it matches (as with the default ls command).
Edit: If you alias your ls to use the command above, it will break the standard ls usage, so you're better off using ephemient's solution if you want your ls usage to always exclude backup files.
For people forced to use ls that doesn't have -B (e.g., using BSD ls in Mac OS X), you can create an alias to a bash function that is based on Mansoor Siddiqui's suggestion. If you add the following function to your bash profile where you keep your aliases (.bash_profile, .profile, .bashrc, .bash_aliases, or equivalent):
ls_no_hidden() {
nonflagcount=0
ARG_ARRAY=(${#})
flags="-l"
curdir=`pwd`
shopt -s nullglob
# Iterate through args, find all flags (arg starting with dash (-))
for (( i = 0; i < $# ; i++ )); do
if [[ ${ARG_ARRAY[${i}]} == -* ]]; then
flags="${flags} ${ARG_ARRAY[${i}]}";
else
((nonflagcount++));
fi
done
if [[ $nonflagcount -eq 0 ]]; then
# ls current directory if no non-flag args provided
FILES=`echo *[^~#]`
# check if files are present, before calling ls
# to suppress errors if no matches.
if [[ -n $FILES ]]; then
ls $flags -d *[^~#]
fi
else
# loop through all args, and run ls for each non-flag
for (( i = 0; i < $# ; i++ )); do
if [[ ${ARG_ARRAY[${i}]} != -* ]]; then
# if directory, enter the directory
if [[ -d ${ARG_ARRAY[${i}]} ]]; then
cd ${ARG_ARRAY[${i}]}
# check that the cd was successful before calling ls
if [[ $? -eq 0 ]]; then
pwd # print directory you are listing (feel free to comment out)
FILES=`echo *[^~#]`
if [[ -n $FILES ]]; then
ls $flags -d *[^~#]
fi
cd $curdir
fi
else
# if file list the file
if [[ -f ${ARG_ARRAY[${i}]} ]]; then
ls $flags ${ARG_ARRAY[${i}]}
else
echo "Directory/File not found: ${ARG_ARRAY[${i}]}"
fi
fi
fi
done
fi
}
alias l=ls_no_hidden
Then l will be mapped to ls but not show files that end in ~ or #.

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