Shell Programming and Scripting

find <directory name> -name "*.log" -mtime +5 -exec rm {} \;
 
If you are using Oracle 11g or higher you may want to consider using
adrci. Here is a script that I wrote.
 
cat purge_adrci.ksh
===============
 
# Description:
# The following script provides to remove log and trace files generated in 11G.
#
# Notes:
#
# 1) That the purge time is in seconds but we prompt for days and convert
# to seconds (since that is how the adrci utilty works), to make things easier.
#
# 2) Second thing to take note of is that adrci works at the file level and if
# that file has been accessed in the number of minutes you specify in the purge
# command. Having said that, adrci will not remove sections of data from the
# alert log that meets the time criteria. Since the alert.log and the log.xml
# are typically updated quite frequently, they will probably not be removed.

 
GetOracleVersion()
{

   if [ -n "$SCRIPT_PATH" ]
   then
      eval $SCRIPT_PATH
   fi
oracle_version=`sqlplus -s / <<END
set pagesize 0 feedback off verify off heading off echo off;
select version FROM v\\$instance;
exit;
END`
echo "$oracle_version"
}
 
Check_DB_Version()
{
   if [ -n "$SCRIPT_PATH" ]
   then
      eval $SCRIPT_PATH
   fi
   oracle_version=$(GetOracleVersion)
   let support_UTSCDMP=0
   if $(CompareVersions "$oracle_version" "<" "10.0")
   then
     return 1
   else
      if $(CompareVersions "$oracle_version" ">=" "11.2")
      then
       #
       # 11g R2: new: -type UTSCDMP, for removing cdmp_* directories
       #
       let support_UTSCDMP=1
      fi
   fi
   return 0
}

 
Convert_Days_To_Minutes()
{
   if [ -n "$SCRIPT_PATH" ]
   then
      eval $SCRIPT_PATH
   fi
   if [ "$days" -lt 1 ]
        then
                echo "Number of days to purge must be specified" >> $ERR_FILE
                return 1
        else
          if [[ "$days" = +([[:digit:]]) ]]
          then
                Minutes=`expr $days \* 1440`
          else
                echo "'$days' is not numeric value for days to purge" >> $ERR_FILE
                return 1
          fi
        fi
        return 0
}
 
GetAWK()
{

  if [ -n "$SCRIPT_PATH" ]
  then
     eval $SCRIPT_PATH
  fi
  whence  nawk > /dev/null
  if [ $? -eq 0 ]
  then
      echo "nawk"
  else
      whence awk > /dev/null
      if [ $? -eq 0 ]
      then
           echo "awk"
      else
          echo "gawk"
      fi
  fi
}
 
CompareVersions()
{
   if [ -n "$SCRIPT_PATH" ]
   then
      eval $SCRIPT_PATH
   fi
   if [ $# -ne 3 ]
   then
      # incorrect number of arguments passed in.
      return 1
   fi
   operand=$2
   # First we compare the two numbers.
   # This will give us a return status of 255, 0 or 1.
   # 255 means arg1 < arg2
   # 0 means arg1 = arg2
   # 1 means arg1 > arg2
   VersionNumCompare $1 $3
   return_status=$?
   if [ ${return_status} -eq 0 ]
   then
      # This means that the both versions are equal to each other.
      # we now need to check if the caller wants the arguments to be
      # equal or not.
      if [ "$operand" = "=" ] || [ "$operand" = "==" ] ||
         [ "$operand" = ">=" ] || [ "$operand" = "<=" ]
      then
         return 0
      else
         return 1
      fi
   elif [ ${return_status} -eq 1 ]
   then
      # This means that the first version is greater than the
      # second version, so we now check if that is what the caller
      # wanted.
      if [ "$operand" = ">" ] || [ "$operand" = ">=" ]
      then
         return 0
      else
         return 1
      fi
   else # return_status is 255
      # If we got here, the first version is lower than the second
      # version, so we check if the caller wanted it to be so.
      if [ "$operand" = "<" ] || [ "$operand" = "<=" ]
      then
         return 0
      else
         return 1
      fi
   fi
}
#
# This function compares two Versions.
#
# Arguments:
#   1: Version with dots "." separating the subversions.
#      Example: "1.2.3.4" or "00001.0002.03.4"
#   2: Same as the argument 1.
#
# Returns:
#   0: If the versions are equivalent.
#   1: If the second version is lower.
#   255: If the first version is lower.
#
VersionNumCompare()
{
   if [ -n "$SCRIPT_PATH" ]
   then
      eval $SCRIPT_PATH
   fi
   if [ $# -ne 2 ]
   then
      # incorrect number of arguments passed in.
      return 255
   fi
   AWK=$(GetAWK)
   echo $* | $AWK ' {
      version1n=split($1, version1, ".");
      version2n=split($2, version2, ".");
      if ( version1n > version2n )
         commonParts=version2n;
      else
         commonParts=version1n;
      i=1;
      while ( i <= commonParts )
      {
         if ( version1[i] < version2[i] )
            exit 255;
         else if (version1[i] > version2[i] )
            exit 1;
         i=i+1;
      }
      # so far everything is equal.
      while ( i <= version1n )
      {
         if ( version1[i] != 0 )
            exit 1;
         i=i+1;
      }
      while ( i <= version2n )
      {
         if ( version2[i] != 0 )
            exit 255;
         i=i+1;
      }
      # everything is equal
      exit 0
   } '
}
 
 
purge_ardci()
{
        timestamp=`date +"%Y-%m-%d %H:%M:%S"`
        echo "adrci purge started at $timestamp"
        # Purge ADR contents
        adrci exec="show homes"|grep -v : | while read file_line
        do
          echo "adrci purging diagnostic destination " $file_line
          echo "purging ALERT older than $days days ..."
          adrci exec="set homepath $file_line;purge -age $Minutes -type ALERT"
          echo "purging INCIDENT older than $days days ..."
          adrci exec="set homepath $file_line;purge -age $Minutes -type INCIDENT"
          echo "purging TRACE older than $days days ..."
          adrci exec="set homepath $file_line;purge -age $Minutes -type TRACE"
          echo "purging CDUMP older than $days days ..."
          adrci exec="set homepath $file_line;purge -age $Minutes -type CDUMP"
          echo "purging HM older than $days days ..."
          adrci exec="set homepath $file_line;purge -age $Minutes -type HM"
          if [ $support_UTSCDMP -eq 1 ]
          then
             echo "purging UTSCDMP older than $days days ..."
             adrci exec="set homepath $file_line;purge -age $Minutes -type UTSCDMP"
          fi
          echo "\n"
        done
        timestamp=`date +"%Y-%m-%d %H:%M:%S"`
        echo "adrci purge completed at $timestamp"
} 
 
 
let days=0
let Minutes=0
# Examine options
while getopts d:s: OPTS; do
  case "$OPTS" in
  d)    days=$OPTARG;;
  s)    ORACLE_SID=$OPTARG;;
  *)    usage
        return 2;;                     # Invalid args
  esac
  done
shift `expr $OPTIND - 1`               # remove argument(s)

 
Convert_Days_To_Minutes
if [ $? -ne 0 ]
then
  return 1
fi
Check_DB_Version
if [ $? -ne 0 ]
then
  echo "ardci not supported for release "$oracle_version" " >> $ERR_FILE
  return 1
fi
purge_ardci