From: Steinar H. Gunderson <sgunderson@bigfoot.com>
Date: Thu, 11 Dec 2014 00:00:47 +0000 (+0100)
Subject: Add some shell magic to split a PGN file into almost equal pieces.
X-Git-Url: https://git.sesse.net/?a=commitdiff_plain;h=b3c16087f728142f36620ed6be3919e7a551e261;p=remoteglot-book

Add some shell magic to split a PGN file into almost equal pieces.
---

diff --git a/partition-pgn.sh b/partition-pgn.sh
new file mode 100755
index 0000000..1c73ca4
--- /dev/null
+++ b/partition-pgn.sh
@@ -0,0 +1,31 @@
+#! /bin/sh
+FILE=$1
+P=$2
+NUM=$3
+
+split_point() {
+	FILE=$1
+	P=$2
+	NUM=$3
+	SIZE=$( stat -c %s "$FILE" )
+
+	if [ "$P" -eq "0" ]; then
+		echo 0
+	elif [ "$P" -eq "$NUM" ]; then
+		echo $SIZE
+	else 
+		TENTATIVE_SPLIT_POINT=$(( SIZE * P / NUM ))
+		OFFS=$( tail -c +${TENTATIVE_SPLIT_POINT} "$FILE" | grep -b '^$' | head -n 1 | cut -d: -f1 )
+		if [ -z "$OFFS" ]; then
+			echo $SIZE
+		else
+			echo $(( TENTATIVE_SPLIT_POINT + OFFS ))
+		fi
+	fi
+}
+
+FROM=$( split_point "$FILE" $P $NUM )
+TO=$( split_point "$FILE" $(( P + 1 )) $NUM )
+SIZE=$(( TO - FROM ))
+
+tail -c +$FROM "$FILE" | head -c $SIZE