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just a little script, or a bit of a template of one that I used to submit an assignment.
I believe it all works fine, I just wanted to give it to other people, and get some feedback on it; maybe make some improvements. I have several variations of the main check_hash function. I've included two of them here today and it's the main element that I'd like some feedback on. Not necessarily just for the sake of this one script, but more to help me design/write better scripts in the future.

I couldn't really decide if I ought to hardcode the variables in place (like variation #1), or make them more modular and have the take arguments (like variation #2). You can have static values like I have here, or you could read values in to the script or accept positional parameters or adapt it however you like.

Some bits have been commented out. I just used them while testing bits and pieces, and thought i'd leave them there for quick debugging in the future. You probably want to know about md5 vs md5sum: I was taking a class on on Unix & C Programming, where we use a bunch of different UNIX-based systems. Some (macOS, most notably), don't have a native md5sum utility, but they have a similar utility just called md5. So that's all that is.

It's not really supposed to be some kind of security / protection mechanism, It's more just to verify file integrity and ensure it's not corrupt. #preamble

#!/usr/bin/env bash
directory='2CvAwTx'
tarball="$directory.tar.gz"
md5='135c72bc1e201819941072fcea882d6f'
sha='318e96fd35806cd008fe79732edba00908fcbeff'

#check_hash function ###variant #1

################################################################################
check_hash ()
{
 ############################################################################
 check_md5 () 
 { 
 if [[ "$(command -v md5)" ]];
 then [[ "$(md5 ./"$tarball" | awk '{print 4ドル}')" == "$md5" ]] ;
 elif [[ "$(command -v md5sum)" ]];
 then [[ "$(md5sum ./"$tarball" | awk '{print 1ドル}')" == "$md5" ]] ;
 fi
 }
 ############################################################################
 check_sha ()
 {
 [[ "$(shasum ./"$tarball" | awk '{print 1ドル}')" == "$sha" ]] ;
 }
 ############################################################################
 check_md5 "$@" ||
 check_sha "$@" ;
}
################################################################################
# check_hash &&
# printf '%s\n' 'true' ||
# printf '%s\n' 'false' ;

###variant #2

################################################################################
check_hash ()
{
 ############################################################################
 check_md5 () 
 {
 if [[ "$(command -v md5)" ]] ;
 then read -r hash _ < <(md5 -q "1ドル") ;
 [[ $hash == "2ドル" ]] ;
 elif [[ "$(command -v md5sum)" ]] ;
 then read -r hash _ < <(md5sum "1ドル") ;
 [[ $hash == "2ドル" ]] ;
 fi
 }
 ############################################################################
 check_sha ()
 {
 read -r hash _ < <(shasum "1ドル") ;
 [[ $hash == "2ドル" ]] ;
 }
 ############################################################################
 check_md5 "$@" || 
 check_sha "$@" ;
}
################################################################################
# check_hash ./"$tarball" "$md5" ||
# check_hash ./"$tarball" "$sha" &&
# printf '%s\n' 'true' ||
# printf '%s\n' 'false' ;

#the part where the things do the stuff

wget "http://www.example.com/$tarball" &&
check_hash "$tarball" "$md5" && 
tar -xzf "$tarball" &&
cd "$directory" &&
make && make clean &&
./a.out