Updated trunc version from Mikko Rauhala.

1 files changed, 25 insertions, 11 deletions

diff --git a/trunc b/trunc
index 6217614..51b62c4 100755..100644
--- a/trunc
+++ b/trunc
@@ -1,6 +1,6 @@
 #!/bin/sh
 
-#	trunc v.1.0rc1 - Truncate a file to a given length
+#	trunc v.1.0 - Truncate a file to a given length
 #
 #	Copyright Mikko Rauhala <mjr@iki.fi>, 2009
 #
@@ -29,7 +29,8 @@
 usage()
 {
 cat 1>&2 << EOF
-Usage: trunc [-b blocksize] size file(s)
+Usage:	trunc [-b blocksize] size file(s)
+	trunc [--help|-h|--version|-v]
 
 Files will be truncated to the given size. Size is given in bytes
 by default, but another block size may also be spesified. If a
@@ -57,31 +58,47 @@ exit 0
 # tasks. We merely tell dd to seek the output file to the given
 # position and write nothing.
 
+# There are some idiosyncracies in this script; most of them can be
+# explained by me having started scripting first in the mid-90s and
+# not bothering to properly find out which of the nicer constructs
+# are bashims (which I want to avoid). Yeah, I'm a lazy bastard.
+
 #	History:
 
+# 1.0		Initial release. Slightly cleaned up from rc1 though
+#		no actual bugs were found. While cleaning, added also
+#		-v and -h.
 # 1.0rc1	Initial release candidate. Will be named 1.0 later if
 #		no bugs are found.
 
 
 # Make sure locale settings don't interfere. Might need to rethink and
 # isolate this setting to smaller parts of the script if this ever gets 
-# localized, but for now, it's okay. (Probably unnecessary here anyway.)
+# localized, but for now, it's okay. (Probably unnecessary in this
+# script anyway, I don't _think_ we're doing anything locale-spesific,
+# but I've taken this habit to be sure. Doesn't hurt.)
 LC_ALL=C
 export LC_ALL
 
-RETVAL=0
-
 ohnoes()
 {
 	echo "trunc: $1" 1>&2
 	exit "$2"
 }
 
-if ! which dd > /dev/null
-then
+if ! which dd > /dev/null; then
 	ohnoes "dd not found (why, oh why?)" 3
 fi
 
+if [ "a$1" = "a-h" -o "a$1" = "a--help" ]; then
+	usage
+fi
+
+if [ "a$1" = "a-v" -o "a$1" = "a--version" ]; then
+	echo "trunc 1.0 by Mikko Rauhala <mjr@iki.fi>" 1>&2
+	exit 0
+fi
+
 BS=1
 if [ "a$1" = "a-b" ]; then
 	if [ "a$2" = "a" ]; then
@@ -99,14 +116,11 @@ fi
 
 SIZE="$1"
 shift
-FILE="$1"
 
-while [ "a$FILE" != a ]; do
+for FILE in "$@"; do
 	if ! ERROR="`dd if=/dev/null of="$FILE" bs="$BS" count=0 seek="$SIZE" 2>&1`"; then 
 		ohnoes "$ERROR" 1
 	fi
-	shift
-	FILE="$1"
 done
 
 exit 0