Apply runtime shebanging to POSIX shell

1 files changed, 27 insertions, 0 deletions

diff --git a/bin/ax.sh b/bin/ax.sh
new file mode 100644
index 00000000..6ce1e9ea
--- /dev/null
+++ b/bin/ax.sh
@@ -0,0 +1,27 @@
+# Evaluate an Awk expression given on the command line with an optional format
+
+# Count arguments
+case $# in
+
+    # If one argument, we assume format is %s
+    1) form=%s expr=$1 ;;
+
+    # If two arguments, first is format, second expression
+    2) form=$1 expr=$2 ;;
+
+    # Any other number of arguments is wrong
+    *)
+        printf >&2 'ax: Need an expression\n'
+        exit 2
+        ;;
+esac
+
+# Form program
+prog=$(printf '
+    BEGIN {
+        printf "%s\\n", %s
+    }
+' "$form" "$expr")
+
+# Run program
+awk "$prog"