This will save parsing time for operations on very big files.
works where perl works, because the awk version is gnu awk only. Show Sample Output
Format of the response: [-]HH:mm Show Sample Output
echo 'Current hour' hour=$(date +%H) if [ $hour -gt 9 -a $hour -lt 23 ]; then echo -n '*'; else echo -n '#'; fi; echo ' '$hour; echo 'Test around the clock:' for hour in {0..23} {0..23}; do if [ $hour -gt 9 -a $hour -lt 23 ]; then echo -n '*'; else echo -n '#'; fi; echo ' '$hour; done echo 'If you need to depend on UTC, just add `-u` flag to `date` command' Show Sample Output
Outputs the real time it takes a Redis ping to run in thousands of a second without any proceeding 0's. Useful for logging or scripted action.
This example is taken from Cygwin running on Win7Ent-64. Device names will vary by platform. Both commands resulted in identical files per the output of md5sum, and ran in the same time down to the second (2m45s), less than 100ms apart. I timed the commands with 'time', which added before 'dd' or 'readom' gives execution times after the command completes. See 'man time' for more info...it can be found on any Unix or Linux newer than 1973. Yeah, that means everywhere. readom is supposed to guarantee good reads, and does support flags for bypassing bad blocks where dd will either fail or hang. readom's verbosity gave more interesting output than dd. On Cygwin, my attempt with 'readom' from the first answer actually ended up reading my hard drive. Both attempts got to 5GB before I killed them, seeing as that is past any CD or standard DVD. dd: 'bs=1M' says "read 1MB into RAM from source, then write that 1MB to output. I also tested 10MB, which shaved the time down to 2m42s. 'if=/dev/scd0' selects Cygwin's representation of the first CD-ROM drive. 'of=./filename.iso' simply means "create filename.iso in the current directory." readom: '-v' says "be a little noisy (verbose)." The man page implies more verbosity with more 'v's, e.g. -vvv. dev='D:' in Cygwin explicitly specifies the D-drive. I tried other entries, like '/dev/scd0' and '2,0', but both read from my hard drive instead of the CD-ROM. I imagine my LUN-foo (2,0) was off for my system, but on Cygwin 'D:' sort of "cut to the chase" and did the job. f='./filename.iso' specifies the output file. speed=2 simply sets the speed at which the CD is read. I also tried 4, which ran the exact same 2m45s. retries=8 simply means try reading a block up to 8 times before giving up. This is useful for damaged media (scratches, glue lines, etc.), allowing you to automatically "get everything that can be copied" so you at least have most of the data. Show Sample Output
Change HH:MM with your target time. This is for a Debian/Ubuntu GNU system. You need bash (package bash), date (package coreutils) and toilet (package toilet). Install with: # apt-get install bash coreutils toilet toilet-fonts
Run this within a steady screen session. You can get the approximate time when the remote server went down or other abnormal behavior.
uses the -u switch for UTC
Another way could be
echo $(($(date -ud "00:29:36" +%s)%86400))
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