home.md

@@ -21,4 +21,30 @@ It is composed by three different part
 
 Let's take a look of what they do, and how to use them.
 
+### magicCut
+Input:
+- trace name
+- number of time steps
+
+Output:
+- cut trace of the best time-step
+- list of functions traced and the correspondent extraes ID ( sometimes it is useful to check that everything is ok)
+
+First of all checks that there are functions in the trace
+```bash
+# grep through prv file if functions are there
+func_check=`grep -m 1 60000019 ${pcf_trace_file} | wc -l`
+```
+Then it reads the .pcf file and creates a file (`FUNCTION_ID_NAMES.txt`) where the IDs that extrae uses are stored along with function's names.
+
+Then, using grep, creates a file with all the lines trace lines relative to functions:
+```bash
+  # Retrieve function's ID
+  echo "Retrieve function's ID"
+  grep  ':60000019:'  ${trace_file}  |  grep -v ':0:'  |  awk -F : '{print $2, $6, $8}' > ${CPU_T_ID}
+```
+1. `grep  ':60000019:'  ${trace_file}` select the function lines
+2. ` grep -v ':0:' ` exclude the line relative to entering and exiting a function
+3. `awk -F : '{print $2, $6, $8}'` select the columns relative to CPU number, time and function ID
+
 [... to be continued]