func might work - first try

1 files changed, 33 insertions, 0 deletions

diff --git a/func/deriveTimeString.sh b/func/deriveTimeString.sh
new file mode 100755
index 0000000..5cb8386
--- /dev/null
+++ b/func/deriveTimeString.sh
@@ -0,0 +1,33 @@
+
+# BOM releases four synoptic charts per day.
+# They are named according to the UTC dat/time for which they are valid.
+#
+# Filenames follow this template: IDY00030.YYYYMMDDHHMM.[png|pdf]
+#
+# IDY00030 = the asset name (i.e. the Mean Sea Level Pressure synoptic chart)
+# .
+# <datetime string>
+# .
+# <extension>  (I want pdf because it contains a Scalable Vectort Graphic (SVG) image)
+
+
+# This function returns the filename for the most recent chart.
+
+DeriveTime() {
+    nowDate=$(\date -u +%y%m%d)   # backslash req. to unalias date to raw format
+    nowTime=$(\date -u +%H%M)     # (I have date aliased to date -R)
+    echo $nowDate$nowTime
+
+    if [ $nowTime -gt 1800 ] ; then
+        fileTime=1800
+    elif [ $nowTime -gt 1200 ] ; then
+        fileTime=1200
+    elif [ $nowTime -gt 0600 ] ; then
+        fileTime=0600
+    else
+        fileTime=0000
+    fi
+
+    echo $nowDate$fileTime
+}
+