new

LDP/guide/docbook/abs-guide/dialog.sh

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+#!/bin/bash
+# dialog.sh: Using 'gdialog' widgets.
+# Must have 'gdialog' installed on your system to run this script.
+
+# This script was inspired by the following article.
+#     "Scripting for X Productivity," by Marco Fioretti,
+#      LINUX JOURNAL, Issue 113, September 2003, pp. 86-9.
+# Thank you, all you good people at LJ.
+
+
+#Input error in dialog box.
+E_INPUT=65
+# Dimensions of display, input widgets.
+HEIGHT=50
+WIDTH=60
+
+# Output file name (constructed out of script name).
+OUTFILE=$0.output
+
+# Display this script in a text widget.
+gdialog --title "Displaying: $0" --textbox $0 $HEIGHT $WIDTH
+
+
+# Now, we'll try saving input in a file.
+echo -n "VARIABLE=\"" > $OUTFILE   # Quote it, in case of whitespace
+                                   #+ in the input.
+gdialog --title "User Input" --inputbox "Enter variable, please:" \
+$HEIGHT $WIDTH 2>> $OUTFILE
+
+
+if [ "$?" -eq 0 ]
+# It's good practice to check exit status.
+then
+  echo "Executed \"dialog box\" without errors."
+else
+  echo "Error(s) in \"dialog box\" execution."
+        # Or, clicked on "Cancel", instead of "OK" button.
+  rm $OUTFILE
+  exit $E_INPUT
+fi
+
+
+echo -n "\"" >> $OUTFILE           # End quotes on saved variable.
+#  This command stuck down here in order not to mess up
+#+ exit status, above.
+
+
+# Now, we'll retrieve and display the saved variable.
+. $OUTFILE   # 'Source' the saved file.
+echo "The variable input in the \"input box\" was: "$VARIABLE""
+
+rm $OUTFILE  # Clean up by removing the temp file.
+             # Some applications may need to retain this file.
+
+exit 0

LDP/guide/docbook/abs-guide/generate-script.sh

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+#!/bin/bash
+# generate-script.sh
+# Based on an idea by Albert Reiner.
+
+OUTFILE=generated.sh         # Name of the file to generate.
+
+
+# -----------------------------------------------------------
+# 'Here document containing the body of the generated script.
+(
+cat <<'EOF'
+#!/bin/bash
+
+echo "This is a generated shell script."
+#  Note that since we are inside a subshell,
+#+ we can't access variables in the "outside" script.
+#  Just to prove it . . .
+echo "Generated file will be named: $OUTFILE"  # Won't work.
+
+a=7
+b=3
+
+let "c = $a * $b"
+echo "c = $c"
+
+exit 0
+EOF
+) > $OUTFILE
+# -----------------------------------------------------------
+
+#  Quoting the 'limit string' prevents variable expansion
+#+ within the body of the above 'here document.'
+#  This permits outputting literal strings in the output file.
+
+if [ -f "$OUTFILE" ]
+then
+  chmod 755 $OUTFILE
+  # Make the generated file executable.
+else
+  echo "Problem in creating file: \"$OUTFILE\""
+fi
+
+#  This method can also be used for generating
+#+ C programs, Perl programs, Python programs, Makefiles,
+#+ and the like.
+
+exit 0