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Full Discussion: Efficient Text File Writing
Homework and Emergencies Homework & Coursework Questions Efficient Text File Writing Post 302631369 by bakunin on Friday 27th of April 2012 09:02:03 AM
Old 04-27-2012
Scrutinizer is correct, but as there are always several ways in Unix to do something, you could do it with the exec too, if you use ksh (note that this won't work in bash, because bash doesn't have the print command):

Code:
exec 3> /some/output/file   # open the file as I/O channel 3 and clear
                            # its contents if it already exists

print -u3 "some text"       # print some text to channel 3
print -u3 "something else"  # same
...

exec 3>&-                   # close I/O-channel 3

This way you won't have to take care of the first ">" and subsequent ">>" redirections (if you mistakenly use ">" it will clear the file) and you will not have to repeat the output files name over and over again.

You could even influence the content of your output file with some program logic in the script - something the here-document provides little support for. For instance, the following would not be possible with a here-doc:

Code:
exec 3> /some/output/file

print -u3 "first line"
print -u3 "second line"

if [ <some_criteria> ] ; then
     print -u3 "----Optional line------"
fi
print -u3 "third line"

exec 3>&-


In exchange for helping you I'd like to ask you to learn about I/O channels (file descriptors) and redirection in Unix and how to use these. You might want to read this thread as a starter.

I hope this helps.

bakunin
This User Gave Thanks to bakunin For This Post:
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LEARN ABOUT SUSE

drop_text_search_template

DROP TEXT SEARCH 
TEMPLATE(7)					   SQL Commands 				      DROP TEXT SEARCH TEMPLATE(7)

NAME

       DROP TEXT SEARCH TEMPLATE - remove a text search template

SYNOPSIS

       DROP TEXT SEARCH TEMPLATE [ IF EXISTS ] name [ CASCADE | RESTRICT ]

DESCRIPTION

       DROP TEXT SEARCH TEMPLATE drops an existing text search template. You must be a superuser to use this command.

PARAMETERS

       IF EXISTS
	      Do not throw an error if the text search template does not exist.  A notice is issued in this case.

       name   The name (optionally schema-qualified) of an existing text search template.

       CASCADE
	      Automatically drop objects that depend on the text search template.

       RESTRICT
	      Refuse to drop the text search template if any objects depend on it.  This is the default.

EXAMPLES

       Remove the text search template thesaurus:

       DROP TEXT SEARCH TEMPLATE thesaurus;

       This command will not succeed if there are any existing text search dictionaries that use the template. Add CASCADE to drop such dictionar-
       ies along with the template.

COMPATIBILITY

       There is no DROP TEXT SEARCH TEMPLATE statement in the SQL standard.

SEE ALSO

       ALTER TEXT SEARCH TEMPLATE [alter_text_search_template(7)], CREATE TEXT SEARCH TEMPLATE [create_text_search_template(7)]

SQL - Language Statements					    2010-05-14					      DROP TEXT SEARCH TEMPLATE(7)
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