You are most welcome to forum, hope you will enjoy learning here. echo $$ will be used to write PID of the current shell.
So tmp$$ is just a Temporary file created in above code, which is later renamed to actual file. Complete explanation is as follows.
Thanks,
R. Singh
This User Gave Thanks to RavinderSingh13 For This Post:
Hi,
I have a data file with following structure:
a|b|c|d|3|f1|f2|f3
a|b|c|d|5|f1|f2|f3|f4|f5
I want to change this data to:
a|b|c|d|3|f1;f2;f3
a|b|c|d|5|f1;f2;f3;f4;f5
Data in column 5 tells the number of following fields. All fields delimiter after the 5th column needs to be... (6 Replies)
I am trying to use sed to replace specific characters at a specific position in the file with a different value... can this be done?
Example:
File:
A0199999123
A0199999124
A0199999125
Need to replace 99999 in positions 3-7 with 88888.
Any help is appreciated. (5 Replies)
Hi,
I have file as below:
5 6 7
4 8 9
3 5 6
output needs to be another file with 4th column as $1+$2 and 5th column as $3+$4.
sample output file
5 6 7 11 18
4 8 9 12 21
3 5 6 8 14
Anybody have answer
Thanks in advance (3 Replies)
Greetings.
I don't have experience programing scripts. I need to insert a string in a specific position of another string on another file (last.cfg), for example:
File last.cfg before using script:
login_interval=1800
lcs.machinename=client04
File last.cfg after using script:... (4 Replies)
Hello experts,
I am new to this group and to 'SED' and 'AWK'. I have data (text file) with 5 columns (C_1-5) and 100s of lines (only 10 lines are shown below as an example). I have to find or select only the id numbers (C-1) of specific lines with '90' in the same line (of C_3) AND with '20' in... (6 Replies)
Hi all!
I need to change the final e every time when it is present in any word in column 1 to a; moreover, to change the final i again to a in any word in column 1, but just if word in column 2 begins with ha or si.
Here below you can see a sample of my data:
achwa ungeliachwa ungeli 1... (3 Replies)
Hi,
I made following configuration to create user directory:
# authconfig --enablemkhomedir --update
But the directory is created as permission 755, I'd like to modify the script to change directory access permission to 700, where is the script which copies /etc/skel to /home... (0 Replies)
Hello,
i need help with awk.
I have this file:
cat number
DirB port 67 er_enc_out 0 er_bad_os 0
DirB port 71 er_enc_out 56 er_bad_os 0
DirB port 74 er_enc_out 0 er_bad_os 0
DirB port 75 ... (4 Replies)
What is the proper syntax to add specific text to a column in a file? Both the input and output below are tab-delineated. What if there are multiple text/fields, such as /CP&/2 /CM&/3 /AA&/4 Thank you :).
sed 's/*/Index&/1' del.txt.hg19_multianno.txt > matrix.del.txt (4 Replies)
Discussion started by: cmccabe
4 Replies
LEARN ABOUT OSX
mktemp
MKTEMP(1) BSD General Commands Manual MKTEMP(1)NAME
mktemp -- make temporary file name (unique)
SYNOPSIS
mktemp [-d] [-q] [-t prefix] [-u] template ...
mktemp [-d] [-q] [-u] -t prefix
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 selecting 1 of 56800235584 (62 ** 6) pos-
sible file names.
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. Care should be taken to ensure that it is appropriate to use an environment variable poten-
tially supplied by the user.
Any number of temporary files may be created in a single invocation, including one based on the internal template resulting from the -t flag.
The mktemp utility 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.
-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 0 on success, and 1 if an error occurs.
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.
tempfoo=`basename $0`
TMPFILE=`mktemp /tmp/${tempfoo}.XXXXXX` || exit 1
echo "program output" >> $TMPFILE
To allow the use of $TMPDIR:
tempfoo=`basename $0`
TMPFILE=`mktemp -t ${tempfoo}` || exit 1
echo "program output" >> $TMPFILE
In this case, we want the script to catch the error itself.
tempfoo=`basename $0`
TMPFILE=`mktemp -q /tmp/${tempfoo}.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
A mktemp utility appeared in OpenBSD 2.1. This implementation was written independently based on the OpenBSD man page, and first appeared in
FreeBSD 2.2.7. This man page is taken from OpenBSD.
BSD December 30, 2005 BSD