1 files changed, 69 insertions, 0 deletions
diff --git a/awklib/eg/prog/id.awk b/awklib/eg/prog/id.awk
new file mode 100644
index 00000000..b29ef61a
--- /dev/null
+++ b/awklib/eg/prog/id.awk
@@ -0,0 +1,69 @@
+# id.awk --- implement id in awk
+# Arnold Robbins, arnold@gnu.ai.mit.edu, Public Domain
+# May 1993
+
+# output is:
+# uid=12(foo) euid=34(bar) gid=3(baz) \
+#             egid=5(blat) groups=9(nine),2(two),1(one)
+
+BEGIN    \
+{
+    if ((getline < "/dev/user") < 0) {
+        err = "id: no /dev/user support - cannot run"
+        print err > "/dev/stderr"
+        exit 1
+    }
+    close("/dev/user")
+
+    uid = $1
+    euid = $2
+    gid = $3
+    egid = $4
+
+    printf("uid=%d", uid)
+    pw = getpwuid(uid)
+    if (pw != "") {
+        split(pw, a, ":")
+        printf("(%s)", a[1])
+    }
+
+    if (euid != uid) {
+        printf(" euid=%d", euid)
+        pw = getpwuid(euid)
+        if (pw != "") {
+            split(pw, a, ":")
+            printf("(%s)", a[1])
+        }
+    }
+
+    printf(" gid=%d", gid)
+    pw = getgrgid(gid)
+    if (pw != "") {
+        split(pw, a, ":")
+        printf("(%s)", a[1])
+    }
+
+    if (egid != gid) {
+        printf(" egid=%d", egid)
+        pw = getgrgid(egid)
+        if (pw != "") {
+            split(pw, a, ":")
+            printf("(%s)", a[1])
+        }
+    }
+
+    if (NF > 4) {
+        printf(" groups=");
+        for (i = 5; i <= NF; i++) {
+            printf("%d", $i)
+            pw = getgrgid($i)
+            if (pw != "") {
+                split(pw, a, ":")
+                printf("(%s)", a[1])
+            }
+            if (i < NF)
+                printf(",")
+        }
+    }
+    print ""
+}