01-30-2009
From perldoc perlop
Quote:
qx/STRING/
`STRING`
A string which is (possibly) interpolated and then executed as a system command with "/bin/sh" or its equivalent. Shell wildcards, pipes, and redirections will be honored. The collected standard output of the command is returned; standard error is unaffected. In scalar context, it comes back as a single (potentially multi-line) string, or undef if the command failed. In list context, returns a list of lines (however you've defined lines with $/ or $INPUT_RECORD_SEPARATOR), or an empty list if the command failed.
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
if ( system ("/bin/cat $File1 >> $File2") ) {
print("#WARNING RAISED : /bin/cat File1 >> File2 - FAILURE!\n"); } I came across this code, would appreciate if someone can tell me if my understanding is correct?
the perl code tell the system to cat file 1 into file 2, if command fails, print... (4 Replies)
Discussion started by: new2ss
4 Replies
2. UNIX for Dummies Questions & Answers
I am totally new to unix commands but I need to understand the following command which is a part of a perl script..what does this mean?
myPwd = $(pwd)
myTracker = $myPwd/myTracker.out
exec > $myTracker 2>&1 (1 Reply)
Discussion started by: athri
1 Replies
3. UNIX for Dummies Questions & Answers
Hi, I need help again. When I run this shell script, it only runs the unld_date.sql piece and exits. How can I structure this to run all the way to the end? When I don't have the unld_date.sql piece in here, everything runs fine from the date compare piece all the way to the end. Thanks in... (5 Replies)
Discussion started by: siog
5 Replies
4. UNIX for Dummies Questions & Answers
I am able to run the UNIX commands in a Windows box from a UNIX box through "SSH" functionality. But whenever the SSH connection is established between UNIX and Windows, password for windows box is being asked.
Is there a way to avoid asking password whenever the SSH connection is made? Can I... (1 Reply)
Discussion started by: D.kalpana
1 Replies
5. Programming
Hi,
-How can I get number of files, cpu usage (percentage), memory usage, disk usage, ...etc, using C program ... I can use unix command ( system(command) )but I want the value to be returned back to my C program to use it in my code? How can I do that?
Thanks in advance ... (2 Replies)
Discussion started by: zainab
2 Replies
6. Shell Programming and Scripting
I understand that in order to run basic unix commands I would normally type at the prompt, I would have to use the following format
system(ls -l);
or
exec(ls -l);
But when I actually try to use the command, the script fails to compile and keeps telling me there is an error with this line. ... (1 Reply)
Discussion started by: userix
1 Replies
7. Shell Programming and Scripting
Hi,
I would like to write a script with include more than 6 unix commands.
my script like below:
echo " script started"
ls -ld
bdf | grep "rama"
tail -10 log.txt
...
..
...
now, i want to run above unix commands one by one.
example:
first the ls -ld command will be... (3 Replies)
Discussion started by: koti_rama
3 Replies
8. Shell Programming and Scripting
Executing two unix commads via perl script one after another
e.g: make clean
bsub -i -q short make
have tried using exec but the second command doesnt executes (1 Reply)
Discussion started by: rajroshan
1 Replies
9. Programming
Hi All,
Is there anything wrong with below syntax?
qx {perldoc -v ModuleName.pm | grep -i Description }
BTW, this question is related to Perl.
Thanks. (3 Replies)
Discussion started by: jal_capri
3 Replies
10. Shell Programming and Scripting
Hi All,
I have put a perl script together to go and collect some information from multiple nodes/endpoints. The script works absolutly fine however I want to make it quicker.
You will see in the below that my script calls an expect script called ssh_run_cmd2.exp followed by the IP of... (7 Replies)
Discussion started by: mutley2202
7 Replies
LEARN ABOUT OPENDARWIN
paste
PASTE(1) BSD General Commands Manual PASTE(1)
NAME
paste -- merge corresponding or subsequent lines of files
SYNOPSIS
paste [-s] [-d list] file ...
DESCRIPTION
The paste utility concatenates the corresponding lines of the given input files, replacing all but the last file's newline characters with a
single tab character, and writes the resulting lines to standard output. If end-of-file is reached on an input file while other input files
still contain data, the file is treated as if it were an endless source of empty lines.
The options are as follows:
-d list Use one or more of the provided characters to replace the newline characters instead of the default tab. The characters in list
are used circularly, i.e., when list is exhausted the first character from list is reused. This continues until a line from the
last input file (in default operation) or the last line in each file (using the -s option) is displayed, at which time paste
begins selecting characters from the beginning of list again.
The following special characters can also be used in list:
newline character
tab character
\ backslash character
Empty string (not a null character).
Any other character preceded by a backslash is equivalent to the character itself.
-s Concatenate all of the lines of each separate input file in command line order. The newline character of every line except the
last line in each input file is replaced with the tab character, unless otherwise specified by the -d option.
If '-' is specified for one or more of the input files, the standard input is used; standard input is read one line at a time, circularly,
for each instance of '-'.
EXAMPLES
List the files in the current directory in three columns:
ls | paste - - -
Combine pairs of lines from a file into single lines:
paste -s -d '
' myfile
Number the lines in a file, similar to nl(1):
sed = myfile | paste -s -d '
' - -
Create a colon-separated list of directories named bin, suitable for use in the PATH environment variable:
find / -name bin -type d | paste -s -d : -
DIAGNOSTICS
The paste utility exits 0 on success, and >0 if an error occurs.
SEE ALSO
cut(1), lam(1)
STANDARDS
The paste utility is expected to be IEEE Std 1003.2 (``POSIX.2'') compatible.
HISTORY
A paste command appeared in Version 32V AT&T UNIX.
BUGS
Multibyte character delimiters cannot be specified with the -d option.
BSD
September 20, 2001 BSD