169 lines
4.2 KiB
Bash
Executable File
169 lines
4.2 KiB
Bash
Executable File
#!/usr/bin/ksh
|
|
#
|
|
# AUTHOR: Randy Micahel
|
|
# SCRIPT: mk_unique_filename.ksh
|
|
# DATE: 11/12/2007
|
|
# REV: 1.2.P
|
|
#
|
|
# PLATFORM: Not Platform Dependent
|
|
#
|
|
# EXIT CODES:
|
|
# 0 - Normal script execution
|
|
# 1 - Usage error
|
|
#
|
|
# REV LIST:
|
|
#
|
|
#
|
|
# set -x # Uncomment to debug
|
|
# set -n # Uncomment to debug without any execution
|
|
#
|
|
####################################################
|
|
########## DEFINE FUNCTIONS HERE ###################
|
|
####################################################
|
|
|
|
function usage
|
|
{
|
|
echo "\nUSAGE: $SCRIPT_NAME base_file_name\n"
|
|
}
|
|
|
|
####################################################
|
|
|
|
function get_date_time_stamp
|
|
{
|
|
DATE_STAMP=$(date +'%m%d%y.%H%M%S')
|
|
echo $DATE_STAMP
|
|
}
|
|
|
|
####################################################
|
|
|
|
function get_second
|
|
{
|
|
THIS_SECOND=$(date +%S)
|
|
echo $THIS_SECOND
|
|
}
|
|
|
|
####################################################
|
|
|
|
function in_range_fixed_length_random_number_typeset
|
|
{
|
|
# Create a pseudo-random number less than or equal
|
|
# to the $UPPER_LIMIT value, which is user defined.
|
|
# This function will also pad the output with leading
|
|
# zeros to keep the number of digits consistent using
|
|
# the typeset command.
|
|
|
|
# Find the length of each character string
|
|
|
|
UL_LENGTH=$(echo ${#UPPER_LIMIT})
|
|
|
|
# Fix the length of the RANDOM_NUMBER variable to
|
|
# the length of the UPPER_LIMIT variable, specified
|
|
# by the $UL_LENGTH variable.
|
|
|
|
typeset -Z$UL_LENGTH RANDOM_NUMBER
|
|
|
|
# Create a fixed length pseudo-random number
|
|
|
|
RANDOM_NUMBER=$(($RANDOM % $UPPER_LIMIT + 1))
|
|
|
|
# Return the value of the fixed length $RANDOM_NUMBER
|
|
|
|
echo $RANDOM_NUMBER
|
|
}
|
|
|
|
####################################################
|
|
|
|
function my_program
|
|
{
|
|
# Put anything you want to process in this function. I
|
|
# recommend that you specify an external program of shell
|
|
# script to execute.
|
|
|
|
echo "HELLO WORLD - $DATE_ST" > $UNIQUE_FN &
|
|
|
|
# : # No-Op - Does nothing but has a return code of zero
|
|
}
|
|
|
|
####################################################
|
|
################ BEGINNING OF MAIN #################
|
|
####################################################
|
|
|
|
SCRIPT_NAME=$(basename $0) # Query the system for this script name
|
|
|
|
# Check for the correct number of arguments - exactly 1
|
|
|
|
if (( $# != 1 ))
|
|
then
|
|
echo "\nERROR: Usage error...EXITING..."
|
|
usage
|
|
exit 1
|
|
fi
|
|
|
|
# What filename do we need to make unique?
|
|
|
|
BASE_FN=$1 # Get the BASE filenaname to make unique
|
|
|
|
RANDOM=$$ # Initialize the RANDOM environment variable
|
|
# with the current process ID (PID)
|
|
|
|
UPPER_LIMIT=32767 # Set the UPPER_LIMIT
|
|
|
|
CURRENT_SECOND=99 # Initialize to a non-second
|
|
LAST_SECOND=98 # Initialize to a non-second
|
|
|
|
USED_NUMBERS= # Initialize to null
|
|
|
|
PROCESSING="TRUE" # Initialize to run mode
|
|
|
|
while [[ $PROCESSING = "TRUE" ]]
|
|
do
|
|
DATE_ST=$(get_date_time_stamp) # Get the current date/time
|
|
CURRENT_SECOND=$(get_second) # Get the current second
|
|
|
|
RN=$(in_range_fixed_length_random_number_typeset) # Get a new number
|
|
|
|
# Check to see if we have already used this number this second
|
|
|
|
if (( CURRENT_SECOND == LAST_SECOND ))
|
|
then
|
|
UNIQUE=FALSE # Initialize to FALSE
|
|
while [[ "$UNIQUE" != "TRUE" ]] && [[ ! -z $UNIQUE ]]
|
|
do
|
|
# Has this number already been used this second?
|
|
echo $USED_NUMBERS | grep $RN >/dev/null 2>&1
|
|
if (( $? == 0 ))
|
|
then
|
|
# Has been used...Get another number
|
|
RN=$(in_range_fixed_length_random_number_typeset)
|
|
else
|
|
# Number is unique this second...
|
|
UNIQUE=TRUE
|
|
# Add this numner to the used number list
|
|
USED_NUMBERS="$USED_NUMBERS $RN"
|
|
fi
|
|
done
|
|
else
|
|
USED_NUMBERS= # New second...Reinitialize to null
|
|
fi
|
|
# Assign the unique filename to the UNIQUE_FN variable
|
|
|
|
UNIQUE_FN=${BASE_FN}.${DATE_ST}.$RN
|
|
|
|
echo $UNIQUE_FN # Comment out this line!!
|
|
|
|
LAST_SECOND=$CURRENT_SECOND # Save the last second value
|
|
|
|
# We have a unique filename...
|
|
#
|
|
# PROCESS SOMETHING HERE AND REDIRECT OUTPUT TO $UNIQUE_FN
|
|
#
|
|
my_program
|
|
#
|
|
# IF PROCESSING IS FINISHED ASSIGN "FALSE" to the PROCESSING VARIABLE
|
|
#
|
|
# if [[ $MY_PROCESS = "done" ]]
|
|
# then
|
|
# PROCESSING="FALSE"
|
|
# fi
|
|
done
|