Change clwr(1) to POSIX sh

1 files changed, 14 insertions, 6 deletions

diff --git a/bin/clwr b/bin/clwr
index af39276a..dc045e9d 100755
--- a/bin/clwr
+++ b/bin/clwr
@@ -1,16 +1,24 @@
-#!/usr/bin/env bash
+#!/bin/sh
+# Write lines of terminal input into a file, clearing in between each one
 self=clwr
-if (($# != 1)) ; then
+
+# Check our inputs for sanity
+if [ "$#" -ne 1 ] ; then
     printf >&2 '%s: Need output file\n' "$self"
     exit 2
-elif [[ ! -t 0 ]] ; then
+elif ! [ -t 0 ] ; then
     printf >&2 '%s: stdin not a terminal\n' "$self"
     exit 2
-elif [[ ! -t 1 ]] ; then
+elif ! [ -t 1 ] ; then
     printf >&2 '%s: stdout not a terminal\n' "$self"
     exit 2
 fi
-exec 3>"$1"
-while { clear && IFS= read -er line ; } ; do
+
+# Open a file descriptor onto the output file to save on open(2)/close(2)
+# system calls
+exec 3>"$1" || exit
+
+# Start looping through clearing and accepting lines
+while { tput clear && IFS= read -r line ; } ; do
     printf '%s\n' "$line" >&3
 done