bash_functions

Various bash functions in separate files that can easily be copied into a main project or included as external files

Table of Contents

• logging.sh
  • log()
  • logrotate()
• ip2long.sh
  • INET_ATON()
  • INET_NTOA()
  • INET_BROADCAST()
  • IN_SUBNET()

---

logging.sh

log()

logs events with a customizable timestamp, severity and destination

Example

source logging.sh
log debug "low level message"
log error "important message"

# default settings that can be changed:
log_level=debug
log_file=/var/log/something.log
log_timestamp='%d %b %Y %H:%M:%S %z'

# to send the logs to stderr you can set log_file to /proc/self/fd/2

logrotate()

checks if a logfile needs to be rotated

Example

source logging.sh

# check if the log is too big, and rotate it if necessary
logrotate

# force a rotation of the log files (e.g. when a script starts up)
logrotate force

---

ip2long.sh

INET_ATON()

converts a IP to a long integer

Example

source ip2long
INET_NTOA 127.0.0.1

INET_NTOA()

converts IP in long integer format to a string

Example

source ip2long
INET_NTOA 2130706433

INET_BROADCAST()

calculates the broadcast IP of a network

Example

source ip2long
INET_BROADCAST 10.0.0.0/24

IN_SUBNET()

checks if an IP is in a specific subnet

Example

source ip2long
IN_SUBNET 10.0.0.2 10.0.0.0/24
echo $?

IN_SUBNET 10.0.1.2 10.0.0.0/24
echo $?