How to Force command substitution evaluation in bash? Post: 302970029

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Top Forums Shell Programming and Scripting How to Force command substitution evaluation in bash? Post 302970029 by siegfried on Thursday 31st of March 2016 12:43:22 PM

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03-31-2016

Registered User

RudiC:
I use BUPLOG twice and that is the problem:
Using BUPLOG twice means I call $(BackupRecords --log "$src") twice which means I get two different log file names. And remember, $(BackupRecords --log "$src") is identical to "$(date +'%Y%b%d%H%M%s')".
I get the same results with BackupRecords --log "$src" and "$(date +'%Y%b%d%H%M%s')": multiple file names. So how can I store the current date and time in an environment variable once and use the environment variable multiple times and not have it change.

Thanks
Siegfried

siegfried

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LEARN ABOUT NETBSD

wtmpx

UTMPX(5)						      BSD File Formats Manual							  UTMPX(5)

NAME

     utmpx, wtmpx, lastlogx -- user accounting database

SYNOPSIS

     #include <utmpx.h>

DESCRIPTION

     In contrast to utmp and wtmp, the extended databases in utmpx and wtmpx reserve more space for logging hostnames, and also information on a
     process' ID, termination signal and exit status.

     The <utmpx.h> header defines the structures and functions for logging user.  Currently logged in users are tracked in /var/run/utmpx, a list
     of all logins and logouts, as well as all shutdowns, reboots and date changes, is kept in /var/log/wtmpx, and the last login of each user is
     noted in /var/log/lastlogx.

     The interface to the utmpx file is described in getutxent(3).

     The wtmpx file can grow rapidly on busy systems, and is normally rotated with newsyslog(8).

     In the event of a date change, a shutdown, or a reboot, the following items are logged in the wtmpx file:
	   date        The system time has been manually or automatically updated by date(1).  The command name date is recorded in the field
		       ut_name.  In the field ut_line, the character '|' indicates the time prior to the change, and the character '{' indicates
		       the new time.
	   reboot
	   shutdown    A system reboot or shutdown has been initiated.	The character '~' is placed in the field ut_line, and reboot or shutdown
		       in the field ut_name (see shutdown(8) and reboot(8)), using logwtmpx(3).

FILES

     /var/run/utmpx	The utmpx file.
     /var/log/wtmpx	The wtmpx file.
     /var/log/lastlogx	The lastlogx file.

SEE ALSO

     last(1), login(1), rwho(1), w(1), who(1), endutxent(3), logwtmpx(3), utmp(5), ac(8), init(8), newsyslog(8), reboot(8)

BSD
								 January 31, 2007							       BSD