unitproc/bktemp-setTimeZoneEV

   1 #!/bin/bash
   2
   3 # Desc: Set time zone environment variable TZ
   4
   5 yell() { echo "$0: $*" >&2; } # Yell, Die, Try Three-Fingered Claw technique; # Ref/Attrib: https://stackoverflow.com/a/25515370
   6 die() { yell "$*"; exit 111; }
   7 try() { "$@" || die "cannot $*"; }
   8 setTimeZoneEV(){
   9     # Desc: Set time zone environment variable TZ
  10     # Usage: setTimeZoneEV arg1
  11     # Version 0.1.2
  12     # Input: arg1: 'date'-compatible timezone string (ex: "America/New_York")
  13     #        TZDIR env var (optional; default: "/usr/share/zoneinfo")
  14     # Output: exports TZ
  15     #         exit code 0 on success
  16     #         exit code 1 on incorrect number of arguments
  17     #         exit code 2 if unable to validate arg1
  18     # Depends: yell(), printenv 8.30, bash 5.0.3
  19     # Tested on: Debian 10
  20     local tzDir returnState argTimeZone
  21
  22     argTimeZone="$1"
  23     if ! [[ $# -eq 1 ]]; then
  24         yell "ERROR:Invalid argument count.";
  25         return 1;
  26     fi
  27
  28     # Read TZDIR env var if available
  29     if printenv TZDIR 1>/dev/null 2>&1; then
  30         tzDir="$(printenv TZDIR)";
  31     else
  32         tzDir="/usr/share/zoneinfo";
  33     fi
  34
  35     # Validate TZ string
  36     if ! [[ -f "$tzDir"/"$argTimeZone" ]]; then
  37         yell "ERROR:Invalid time zone argument.";
  38         return 2;
  39     else
  40     # Export ARG1 as TZ environment variable
  41         TZ="$argTimeZone" && export TZ && returnState="true";
  42     fi
  43
  44     # Determine function return code
  45     if [ "$returnState" = "true" ]; then
  46         return 0;
  47     fi
  48 } # Exports TZ environment variable
  49
  50 #==BEGIN sample code==
  51 date --iso-8601=seconds; echo "==============="; sleep 2
  52
  53 date --iso-8601=seconds
  54 cmd1="setTimeZoneEV America/New_York"
  55 echo "Running:$cmd1"; $cmd1; echo "Exit code:$?"
  56 date --iso-8601=seconds; echo "==============="; sleep 2
  57
  58 date --iso-8601=seconds
  59 cmd2="setTimeZoneEV Asia/Tokyo"
  60 echo "Running:$cmd2"; $cmd2; echo "Exit code:$?"
  61 date --iso-8601=seconds; echo "==============="; sleep 2
  62
  63 date --iso-8601=seconds
  64 cmd3="setTimeZoneEV";
  65 echo "Running:$cmd3"; $cmd3; echo "Exit code:$?"
  66 date --iso-8601=seconds; echo "==============="; sleep 2
  67
  68 date --iso-8601=seconds
  69 cmd4="setTimeZoneEV Pacific/Lemuria"
  70 echo "Running:$cmd4"; $cmd4; echo "Exit code:$?"
  71 date --iso-8601=seconds; echo "==============="; sleep 2
  72
  73 try setTimeZoneEV Atlantic/Atlantis
  74 #==END sample code==
  75
  76 # Author: Steven Baltakatei Sandoval
  77 # License: GPLv3+
  78
  79