Simplify source searcher; improve usage example

FossilOrigin-Name: 5aa9f009fe1c9559df42802b2cd19b48af58b23bfd4c4427e480cb3cc89cbb49

Author: programandala-net

src/doc/manual_skeleton.adoc

@@ -10,7 +10,7 @@
 // This file is part of Solo Forth
 // http://programandala.net/en.program.solo_forth.html
 
-// Last modified: 202003012143
+// Last modified: 202003012156
 
 toc::[]
 
@@ -616,12 +616,12 @@ The script uses ``ack`` by default; if ``ack`` is not installed,
 Usage examples:
 
 ----
-tools/search_sources use-thru-index
-tools/search_sources use-thru-index -l
-tools/search_sources color
-tools/search_sources ";\s:\s"
-tools/search_sources "\-bank"
-tools/search_sources "code\s+\S+\s+\("
+./tools/search_sources use-thru-index
+./tools/search_sources use-thru-index -l
+./tools/search_sources color
+./tools/search_sources ";\s:\s"
+./tools/search_sources "\-bank"
+./tools/search_sources "code\s+\S+\s+\("
 ----
 
 // How to test and benchmark {{{1

tools/search_sources

@@ -5,7 +5,7 @@
 # This file is part of Solo Forth
 # http://programandala.net/en.program.solo_forth.html
 
-# Last modified: 202003012113
+# Last modified: 202003012155
 
 # Search the sources of Solo Forth using ack (by default) or grep
 # (when ack is not installed).  All parameters and options are passed
@@ -14,9 +14,7 @@
 # 2020-03-01
 
 dirs="./src/kernel*.z80s ./src/lib/*.fs"
-errors_file=./tmp/search_sources_errors
 
-ack $* -r $dirs 2>$errors_file || \
-grep $* -r $dirs 2>$errors_file
+ack $* -r $dirs 2>/dev/null || \
+grep $* -r $dirs 2>/dev/null
 
-rm -f $errors_file