xml-format.sh:

#!/bin/sh

if [ -z $1 ]; then
	echo "need to provide a command line parameter"
	exit 1
fi

if [ ! -e $1 ]; then
	echo "provided argument \"$1\" does not exist"
	exit 1
fi

# extension=`echo $1 | sed -r 's/[^.]*(\.([^.]*))*$/\2/g'`
#if [ "$extension" != "xml" ]; then
#	echo "script may only be called on xml files, invalid extension \"$extension\""
#	exit 1
#fi

if [ ! -e $1 ]; then
	echo "provided argument \"$1\" does not exist"
	exit 1
fi

# Old instruction for echo:
# echo "XMLLINT_INDENT=\$'\t' xmllint --format \"$1\" > \"$1.formatted\"; mv \"$1.formatted\" \"$1\""

# New instructions: echo and execute
echo "export XMLLINT_INDENT='	'; xmllint --format \"$1\" > \"$1.formatted\"; mv \"$1.formatted\" \"$1\""

export XMLLINT_INDENT='	';
xmllint --format "$1" > "$1.formatted";

# Safeguard: do not overwrite original file unless xmllint succeeded
if [ "$?" = "0" ]; then
  mv "$1.formatted" "$1"
else
  rm "$1.formatted"
fi

guarded-xml-format.sh:

#!/bin/sh

if [ -z $1 ]; then
	echo "need to provide a command line parameter"
	exit 1
fi

if [ ! -e $1 ]; then
	echo "provided argument \"$1\" does not exist"
	exit 1
fi

SCRIPT_PATH=`dirname "$0"`
# echo "SCRIPT_PATH is $SCRIPT_PATH"

EXTENSIONS=""
ALLOWED_EXTENSION="false"

FILE=""
extension="(uninitialized)"

for arg in "$@" ; do
    if [ "$FILE" = "" ]; then
        FILE=$arg
        extension=`echo $FILE | sed -r 's/[^.]*(\.([^.]*))*$/\2/g'`
#         echo "for file $FILE detected extension: $extension"
    else
#         echo "allowed extension: $arg"
        if [ "$EXTENSIONS" != "" ]; then
            EXTENSIONS="$EXTENSIONS, "
        fi
        EXTENSIONS="$EXTENSIONS\"$arg\""
        if [ "$extension" = "$arg" ]; then
#             echo "file name matches allowed extension $arg"
            ALLOWED_EXTENSION="true"
break;
        fi
    fi
done

if [ "$ALLOWED_EXTENSION" = "true" ]; then
#     echo "found an allowed extension - if it safe to invoke $SCRIPT_PATH/xml-format.sh for $FILE"
    "$SCRIPT_PATH/xml-format.sh" $FILE
else
#     echo "script may only be called on files with extensions [$EXTENSIONS], invalid extension \"$extension\" on $FILE"
    exit 1
fi

xml-format-all.sh:

#!/bin/sh

SCRIPT_PATH=`dirname "$0"`
# echo "SCRIPT_PATH is $SCRIPT_PATH"

EXTENSIONS="xml rels"
EXTENSIONS_FOR_ECHO="\"xml\", \"rels\""
for arg in "$@" ; do
    if [ "$arg" != "xml" ] && [ "$arg" != "rels" ]; then
        EXTENSIONS="$EXTENSIONS $arg"
        EXTENSIONS_FOR_ECHO="$EXTENSIONS_FOR_ECHO, \"$arg\""
    else
        echo "ignoring default extension [\"xml\" or \"rels\"]"
    fi
done

echo "applying xmllint recursively to all files in folder ending in any of [$EXTENSIONS_FOR_ECHO]"
# echo "find . -type f -exec $SCRIPT_PATH/guarded-xml-format.sh {} $EXTENSIONS \;"
find . -type f -exec "$SCRIPT_PATH/guarded-xml-format.sh" {} $EXTENSIONS \;

In reply to@m-yusuf:matrix.org
Beginner Q: Seeking a website to get started with Hands-on Bash scripting ? Any inputs are appreciated !

In reply to @euro20179:matrix.org
well ${0%/*} is guaranteed to remove the slash but the former, first finds the basename with 0##*/ and a question mark for some reason, then deletes that from $0 with $0%

p='/'
"${p%?"${p##*/?}"}"  # '/'
"${p%/*}/"           # '/'
"$(dirname "$p")"    # '/'

p=''
"${p%?"${p##*/?}"}"  # ''
"${p%/*}/"           # '/'
"$(dirname "$p")"    # '.'

sh-5.2$ p='/'
sh-5.2$ echo "${p%/*}"

sh-5.2$

sh-5.2$ p='/'
sh-5.2$ echo "${p%/*}"

sh-5.2$

In reply to @benjaminedwardwebb:envs.net
Does anyone here have tips on how to evaluate the performance of a bash function or builtin? My current strategy is simply time for _ in {0..n}; do f; done, but I'd love to find out there is something like hyperfine but for bash builtins

In reply to @benjaminedwardwebb:envs.net
a benchmarking tool with great documentation https://github.com/sharkdp/hyperfine?tab=readme-ov-file#shell-functions-and-aliases