First off, if you write to temporary files you should always prepare a place for these first and clean this place upon exit. Usually you can use the PID variable to make the places name unique, because the PID is always unique. I do it usually the following way (sketch only):
This way each instance of a script gets its own temp dir, puts everything it uses in there and upon exit (regardless which exit, even when terminated from outisde) it cleans up. The only way to have the temp files not cleaned is to terminate it with a "kill -9".
how to make a line BLINKING in output and also how to increase font size in output
suppose in run a.sh script
inside echo "hello world "
i want that this should blink in the output and also
the font size of hello world should be big ..
could you please help me out in this (3 Replies)
I'm new to PERL, but I want to take the page source and write it to a file or standard output. I used perl.org as a test website. Here is the script:
use strict;
use warnings;
use LWP::Simple;
getprint('http://www.perl.org') or die 'Unable to get page';
exit 0;
... (1 Reply)
Hi guys;
TBH I am an absolute novice, when it comes to scripting; I do have an idea of the basic commands...
Here is my problem;
I have a flatfile 'A' containing a single column with multiple rows. I have to create a script which will use 'A' as input and then output a string in in the... (0 Replies)
Hi All,
I have around 900 Select Sql's which I would like to run in an awk script and print the output of those sql's in an txt file.
Can you anyone pls let me know how do I do it and execute the awk script? Thanks. (4 Replies)
I have a list of DNS servers I need to look up information on. Each of these servers has a master and a slave database. Essentially what I need to do is create two text files for each server. One with the Master view and one with the Slave view. There's 20 servers, in the end I should have 40 text... (4 Replies)
Below script perfectly works, giving below mail output. BUT, I want to make the script mail only if there are any D-Defined/T-Transition/B-Broken State WPARs and also to copy the output generated during monitoring to a temporary log file, which gets cleaned up every week. Need suggestions.
... (4 Replies)
Hi All,
I have result log file which looks like this (below): from the content need to consolidate the result and put it in tabular form
1). Intercomponents Checking
Passed: All Server are passed.
======================================================================
2). OS version Checking... (9 Replies)
I ran the following command.
cat abc.c > abc.c
I got message the following message from command cat:
cat: abc.c : input file is same as the output file
How the command came to know of the destination file name as the command is sending output to standard file. (3 Replies)
OS: Linux
kernel ver: 2.6x
shell: Korn(ksh)
hi.
We are required to read contents for mutliple GZIP(.gz) files and perform some custom sanity checks downstream, example of such a check can a validation for the length of each record. We should accepts records which are 320 chars long and... (1 Reply)
Discussion started by: kumarjt
1 Replies
LEARN ABOUT NETBSD
mktemp
MKTEMP(1) BSD General Commands Manual MKTEMP(1)NAME
mktemp -- make temporary file name (unique)
SYNOPSIS
mktemp [-dqu] [-p tmpdir] {-t prefix | template ...}
DESCRIPTION
The mktemp utility takes each of the given file name templates and overwrites a portion of it to create a file name. This file name is
unique and suitable for use by the application. The template may be any file name with some number of 'Xs' appended to it, for example
/tmp/temp.XXXX. The trailing 'Xs' are replaced with the current process number and/or a unique letter combination. The number of unique
file names mktemp can return depends on the number of 'Xs' provided; six 'Xs' will result in mktemp testing roughly 26 ** 6 combinations.
If mktemp can successfully generate a unique file name, the file is created with mode 0600 (unless the -u flag is given) and the filename is
printed to standard output.
If the -t prefix option is given, mktemp will generate a template string based on the prefix and the TMPDIR environment variable, if set.
The default location if TMPDIR is not set is /tmp. The default location of the temporary directory can be overridden with the -p tmpdir
option. The template string created will consist of the prefix followed by a '.' and an eight character unique letter combination. 'Xs' in
the prefix string will be treated as literal. If an additional template argument is passed, a second file will be created. Care should be
taken to ensure that it is appropriate to use an environment variable potentially supplied by the user.
Any number of temporary files may be created in a single invocation using multiple template arguments, also a single one based on the inter-
nal template with the -t option value as filename prefix.
At least one template argument or the -t option must be present.
mktemp is provided to allow shell scripts to safely use temporary files. Traditionally, many shell scripts take the name of the program with
the pid as a suffix and use that as a temporary file name. This kind of naming scheme is predictable and the race condition it creates is
easy for an attacker to win. A safer, though still inferior, approach is to make a temporary directory using the same naming scheme. While
this does allow one to guarantee that a temporary file will not be subverted, it still allows a simple denial of service attack. For these
reasons it is suggested that mktemp be used instead.
OPTIONS
The available options are as follows:
-d Make a directory instead of a file.
-q Fail silently if an error occurs. This is useful if a script does not want error output to go to standard error.
-t prefix
Generate a template (using the supplied prefix and TMPDIR if set) to create a filename template. If -t prefix and template are both
given, prefix will not apply to template.
-u Operate in ``unsafe'' mode. The temp file will be unlinked before mktemp exits. This is slightly better than mktemp(3) but still
introduces a race condition. Use of this option is not encouraged.
EXIT STATUS
The mktemp utility exits with a value of 0 on success, and 1 on any failure.
EXAMPLES
The following sh(1) fragment illustrates a simple use of mktemp where the script should quit if it cannot get a safe temporary file.
TMPFILE=`mktemp /tmp/${0##*/}.XXXXXX` || exit 1
echo "program output" >> $TMPFILE
To allow the use of $TMPDIR:
TMPFILE=`mktemp -t ${0##*/}` || exit 1
echo "program output" >> $TMPFILE
In this case, we want the script to catch the error itself.
TMPFILE=`mktemp -q /tmp/${0##*/}.XXXXXX`
if [ $? -ne 0 ]; then
echo "$0: Can't create temp file, exiting..."
exit 1
fi
SEE ALSO mkdtemp(3), mkstemp(3), mktemp(3), environ(7)HISTORY
The mktemp utility appeared in NetBSD 1.5. It has been imported from FreeBSD, the idea and the manual page were taken from OpenBSD.
BSD August 15, 2009 BSD