1 files changed, 72 insertions, 0 deletions
diff --git a/awklib/eg/prog/extract.awk b/awklib/eg/prog/extract.awk
new file mode 100644
index 00000000..a9f5b80f
--- /dev/null
+++ b/awklib/eg/prog/extract.awk
@@ -0,0 +1,72 @@
+# extract.awk --- extract files and run programs
+#                 from texinfo files
+# Arnold Robbins, arnold@gnu.ai.mit.edu, Public Domain
+# May 1993
+
+BEGIN    { IGNORECASE = 1 }
+
+/^@c(omment)?[ \t]+system/    \
+{
+    if (NF < 3) {
+        e = (FILENAME ":" FNR)
+        e = (e  ": badly formed `system' line")
+        print e > "/dev/stderr"
+        next
+    }
+    $1 = ""
+    $2 = ""
+    stat = system($0)
+    if (stat != 0) {
+        e = (FILENAME ":" FNR)
+        e = (e ": warning: system returned " stat)
+        print e > "/dev/stderr"
+    }
+}
+/^@c(omment)?[ \t]+file/    \
+{
+    if (NF != 3) {
+        e = (FILENAME ":" FNR ": badly formed `file' line")
+        print e > "/dev/stderr"
+        next
+    }
+    if ($3 != curfile) {
+        if (curfile != "")
+            close(curfile)
+        curfile = $3
+    }
+
+    for (;;) {
+        if ((getline line) <= 0)
+            unexpected_eof()
+        if (line ~ /^@c(omment)?[ \t]+endfile/)
+            break
+        else if (line ~ /^@(end[ \t]+)?group/)
+            continue
+        if (index(line, "@") == 0) {
+            print line > curfile
+            continue
+        }
+        n = split(line, a, "@")
+        # if a[1] == "", means leading @,
+        # don't add one back in.
+        for (i = 2; i <= n; i++) {
+            if (a[i] == "") { # was an @@
+                a[i] = "@"
+                if (a[i+1] == "")
+                    i++
+            }
+        }
+        print join(a, 1, n, SUBSEP) > curfile
+    }
+}
+function unexpected_eof()
+{
+    printf("%s:%d: unexpected EOF or error\n", \
+        FILENAME, FNR) > "/dev/stderr"
+    exit 1
+}
+
+END {
+    if (curfile)
+        close(curfile)
+}