bash script error in created command line

I'm trying to make a script which "builds" a configure command line and then runs it, but it fails with an error. I'm very new to bash script (i'm a Windows user) and i don't know what i'm doing wrong.

This is my script:

            #! /bin/sh
        # https://www.guru99.com/introduction-to-shell-scripting.html

        export PKG_CONFIG_PATH=/usr/lib/arm-linux-gnueabihf/pkgconfig

        PARAMS=""
        PARAMS="$PARAMS --disable-shared"
        PARAMS="$PARAMS --disable-debug"
        PARAMS="$PARAMS --with-gtk=2"
        PARAMS="$PARAMS --with-libtiff=no"
        PARAMS="$PARAMS --with-opengl=no"
        PARAMS="$PARAMS --enable-unicode"
        PARAMS="$PARAMS --with-libpng=builtin"
        PARAMS="$PARAMS --with-libjpeg=builtin"
        PARAMS="$PARAMS --enable-std_string_conv_in_wxstring"
        PARAMS="$PARAMS --host=arm-linux-gnueabihf"
        PARAMS="$PARAMS --build=x86_64-linux-gnu"

        GTK_LIBS=$(arm-linux-gnueabihf-pkg-config --libs gtk+-2.0)
        echo "GTK_LIBS = " $GTK_LIBS
        echo
        PARAMS="$PARAMS GTK_LIBS=\"$GTK_LIBS\""

        GTK_CFLAGS=$(arm-linux-gnueabihf-pkg-config --cflags gtk+-2.0)
        echo "GTK_CFLAGS = " $GTK_CFLAGS
        echo

        COMMAND="../configure $PARAMS GTK_CFLAGS=\"$GTK_CFLAGS\""
        echo "COMMAND = " $COMMAND
        echo

        echo "Running COMMAND"
        $COMMAND

This is the output:

GTK_LIBS = -L/usr/lib/arm-linux-gnueabihf -lgtk-x11-2.0 -lgdk-x11-2.0 -lpangocairo-1.0 -latk-1.0 -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lpangoft2-1.0 -lpango-1.0 -lgobject-2.0 -lglib-2.0 -lharfbuzz -lfontconfig -lfreetype

GTK_CFLAGS = -pthread -I/usr/include/gtk-2.0 -I/usr/lib/arm-linux-gnueabihf/gtk-2.0/include -I/usr/include/pango-1.0 -I/usr/include/atk-1.0 -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pango-1.0 -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/fribidi -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/harfbuzz -I/usr/include/glib-2.0 -I/usr/lib/arm-linux-gnueabihf/glib-2.0/include -I/usr/include/uuid -I/usr/include/freetype2 -I/usr/include/libpng16

COMMAND = ../configure --disable-shared --disable-debug --with-gtk=2 --with-libtiff=no --with-opengl=no --enable-unicode --with-libpng=builtin --with-libjpeg=builtin --enable-std_string_conv_in_wxstring --host=arm-linux-gnueabihf --build=x86_64-linux-gnu GTK_LIBS="-L/usr/lib/arm-linux-gnueabihf -lgtk-x11-2.0 -lgdk-x11-2.0 -lpangocairo-1.0 -latk-1.0 -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lpangoft2-1.0 -lpango-1.0 -lgobject-2.0 -lglib-2.0 -lharfbuzz -lfontconfig -lfreetype" GTK_CFLAGS="-pthread -I/usr/include/gtk-2.0 -I/usr/lib/arm-linux-gnueabihf/gtk-2.0/include -I/usr/include/pango-1.0 -I/usr/include/atk-1.0 -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/pango-1.0 -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/fribidi -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/harfbuzz -I/usr/include/glib-2.0 -I/usr/lib/arm-linux-gnueabihf/glib-2.0/include -I/usr/include/uuid -I/usr/include/freetype2 -I/usr/include/libpng16"

Running COMMAND

configure: error: unrecognized option: `-lgtk-x11-2.0'

Try `../configure --help' for more information

I don't understand why there's the error: it seems like i didn't add the doublequotes, but they are there and if i just copy/paste the COMMAND from the output in the prompt it works.

I tried searching for answers here... which managed me to add the escaped quotes in the script, but that's all....

What am i missing?

How about exporting the variables before running the command, instead of them being part of the command?

Try this:

#!/bin/sh
# https://www.guru99.com/introduction-to-shell-scripting.html

export PKG_CONFIG_PATH=/usr/lib/arm-linux-gnueabihf/pkgconfig

PARAMS=""
PARAMS="$PARAMS --disable-shared"
PARAMS="$PARAMS --disable-debug"
PARAMS="$PARAMS --with-gtk=2"
PARAMS="$PARAMS --with-libtiff=no"
PARAMS="$PARAMS --with-opengl=no"
PARAMS="$PARAMS --enable-unicode"
PARAMS="$PARAMS --with-libpng=builtin"
PARAMS="$PARAMS --with-libjpeg=builtin"
PARAMS="$PARAMS --enable-std_string_conv_in_wxstring"
PARAMS="$PARAMS --host=arm-linux-gnueabihf"
PARAMS="$PARAMS --build=x86_64-linux-gnu"

GTK_LIBS=$(arm-linux-gnueabihf-pkg-config --libs gtk+-2.0)
echo "GTK_LIBS = " $GTK_LIBS
echo

GTK_CFLAGS=$(arm-linux-gnueabihf-pkg-config --cflags gtk+-2.0)
echo "GTK_CFLAGS = " $GTK_CFLAGS
echo

COMMAND="../configure $PARAMS"
echo "COMMAND = " $COMMAND
echo

echo "Setting variables and running COMMAND"
export GTK_LIBS
export GTK_CFLAGS
$COMMAND

First, unless you have modified the default Ubuntu /bin/sh, it will be executed as a dash script rather than a bash script.

The issue is that you can't convert a whitespace-containing string into a properly shell-quoted list of tokens by using literal quotes and then leaving the resulting expansion unquoted. Simplifying your code, you're essentially doing:

PARAMS=foo
GTK_LIBS="bar baz"
PARAMS="$PARAMS GTK_LIBS=\"$GTK_LIBS\""

and then expanding $PARAMS without quoting, which (in both bash dash) will result in word splitting into the following literal tokens:

$ printf '%s\n' $PARAMS
foo
GTK_LIBS="bar
baz"

If you actually change the shell to bash then you can get around this using arrays:

#!/bin/bash

PARAMS=("foo")
GTK_LIBS=("bar" "baz")
PARAMS+=(GTK_LIBS="${GTK_LIBS[@]}")

then expand the array as "${PARAMS[@]}", which correctly tokenizes the arguments:

printf '%s\n' "${PARAMS[@]}"
foo
GTK_LIBS=bar baz

See also:

• Why does my shell script choke on whitespace or other special characters?
• How can we run a command stored in a variable?