Grepping strace output gets hard

This is the error you get if you try to search in an empty directory:

$ tree
.
├── dir
│   └── file
└── empty_dir

2 directories, 1 file
$ grep foo dir/*  ## works, no error
$ grep foo empty_dir/*
grep: empty_dir/*: No such file or directory

Basically, when you run something like grep ./*, the glob (*) is interpreted by the shell which will expand it to the contents of the directory you gave. If the directory is empty, that expands to nothing and the shell returns an error. You will get the same error irrespective of which program you use:

$ ls empty_dir/*
ls: cannot access empty_dir/*: No such file or directory

So, I'm guessing that ~/5as-darbas/inputs/multiple_dir/ is empty. This is not a big deal and you can just ignore the error. If you want to deal with it more gracefully, you could give the directory name (no glob) and run a recursive grep:

$ grep -R foo empty_dir/

To do this with your current setup, change `~/5as-darbas/inputs/multiple_dir/* to ~/5as-darbas/inputs/multiple_dir/ and give grep -R as the first argument to your script:

$ myscript.sh 'grep -R' regExp/regExp tests/MULTIPLE.inp outputs/MULTIPLE.out

This would do it i hope. Events go to events file. And messages go to stdout.

Save this file to myprogram.awk (for example):

#!/usr/bin/awk -f

BEGIN {
   s=0;  ### state. Active when parsing inside an event
   nevent=0;  ### Current event number
   printf "" > "events"
}

# Start of event
/^ *Data control raising event/ {
   s=1;
   dentries=0;
   print "*** Event number: " nevent >> "events"
   nevent++
}

# Standard event line
s==1 {
   print >> "events"
}

# DataChangeEntry line
/^ *==== DataChangeEntry/ {
   dentries ++
}

# End of event
s==1 && /^ *\]\]/ {
   s=0;
   print "" >> "events"
   if(dentries==0){
      print "Warning: Event " nevent " has no Data Entries"
   }
}

END {
   print "Total event count: " nevent
}

You can invoke it in different ways:

• myprogram.awk inputfile.txt
• awk -f myprogram.awk inputfile.txt

Sample output:

Warning: Event 3 has no Data Entries
Total event count: 3

You can check all the events together in the file called events in working directory.