Add blackbox_less. (#263)

* Add blackbox_view and use PAGER (default to less)

README.md

@@ -99,6 +99,7 @@ Commands
 | `blackbox_edit_start <file>`        | Decrypt a file so it can be updated                                     |
 | `blackbox_edit_end <file>`          | Encrypt a file after blackbox_edit_start was used                       |
 | `blackbox_cat <file>`               | Decrypt and view the contents of a file                                 |
+| `blackbox_view <file>`              | Like blackbox_cat but pipes to `less` or $PAGER                         |
 | `blackbox_diff`                     | Diff decrypted files against their original crypted version             |
 | `blackbox_initialize`               | Enable blackbox for a GIT or HG repo                                    |
 | `blackbox_register_new_file <file>` | Encrypt a file for the first time                                       |

bin/blackbox_view

@@ -0,0 +1,20 @@
+#!/usr/bin/env bash
+
+#
+# blackbox_view -- Decrypt a file, view it, shred it
+#
+set -e
+source "${0%/*}/_blackbox_common.sh"
+
+for param in "$@" ; do
+  shreddable=0
+  unencrypted_file=$(get_unencrypted_filename "$param")
+  if [[ ! -e "$unencrypted_file" ]]; then
+    "${BLACKBOX_HOME}/blackbox_edit_start" "$param"
+    shreddable=1
+  fi
+  ${PAGER:-less} "$unencrypted_file"
+  if [[ $shreddable = 1 ]]; then
+    shred_file "$unencrypted_file"
+  fi
+done