git-identity.sh: improve usage

[cmccabe-bin] / pickrand.py

diff --git a/pickrand.py b/pickrand.py
index 8253e74..6340971 100755 (executable)
--- a/pickrand.py
+++ b/pickrand.py
@@ -4,14 +4,25 @@ import os
 import random
 import sys
 
+print_to_stderr = False
+if (len(sys.argv) == 1):
+    pass
+elif (len(sys.argv) == 2) and (sys.argv[1] == "-S"):
+    print_to_stderr = True
+else:
+    print >>sys.stderr, "invalid command-line arguments"
+    sys.exit(1)
+
 allfiles = []
 
-for root, dirs, files in os.walk(".", followlinks=True):
+for root, dirs, files in os.walk("."):
     for f in files:
         allfiles.append(os.path.join(root, f))
 if (len(allfiles) == 0):
    sys.exit(1)
-random.seed(None)
-r = random.randint(0,len(allfiles)) 
+random.seed(os.getpid())
+r = random.randint(0,len(allfiles) - 1)
 print(allfiles[r])
+if (print_to_stderr):
+    print >>sys.stderr, (allfiles[r])
 sys.exit(0)