date command getting previous day

swinchen · 08-23-2004, 10:12 AM

Is there any way to get the previous day in linux?

I want something like date +%y%m%d .... but the pervious day.

for example,

date +%y%m%d
040801

but I want the previous day... so it should output

040731

Thanks.

itsme86 · 08-23-2004, 10:43 AM

You can use time(NULL) - 86400; as the current time?

swinchen · 08-23-2004, 11:26 AM

No... that doesnt seem to work....

swinchen · 08-23-2004, 11:30 AM

Found it!!! To get the previous day... do something like this:

date +%y%m%d --date="-1 day"

arvind_sv · 08-23-2004, 11:39 AM

Hi,

Try this:

date +%y%m%d -d '1 day ago'

Arvind

PS: Ah, I see you found it yourself, just when I was replying.

b0ng · 08-23-2004, 11:47 AM

#!/usr/bin/perl

$_ = `date`;

@date = split /\s/;

#print "@date[2]";
@date[2]--;

print "@date\n";

#That should do what you want.

haha, you guys did it while, I was writing my script.

itsme86 · 08-23-2004, 12:17 PM

This is what I meant:

Code:

itsme@dreams:~/C$ cat prevday.c
#include <stdio.h>
#include <time.h>

int main(void)
{
  time_t now;

  now = time(NULL);
  printf("Today is: %s", ctime(&now));
  now -= 86400;
  printf("Yesterday was: %s", ctime(&now));
  return 0;
}
itsme@dreams:~/C$ ./prevday
Today is: Mon Aug 23 10:16:26 2004
Yesterday was: Sun Aug 22 10:16:26 2004