08-28-2008
What is your operating system?
What does the following give?
ls -lrt /dev/null
Check if this works?
ls -ld /usr /foo 2>/directory_where_u_have_permissions_to_write/err.txt
10 More Discussions You Might Find Interesting
1. Shell Programming and Scripting
In bash, I need to send the STDOUT and STDERR from a command to one file, and then just STDERR to another file. Doing one or the other using redirects is easy, but trying to do both at once is a bit tricky. Anyone have any ideas? (9 Replies)
Discussion started by: jshinaman
9 Replies
2. Shell Programming and Scripting
If I forget to set up stderr redirection on execution of a script, is there a way to set that redirection post-exec? In other words, if I have a script running and no errors are being logged... and then I remember that I forgot the 2>&1 on the script... can I turn it on after the fact?
...and... (1 Reply)
Discussion started by: jjinno
1 Replies
3. Shell Programming and Scripting
Friends
I have to redirect STDERR messages both to screen and also capture the same in a file.
2 > &1 | tee file works but it also displays the non error messages to file, while i only need error messages.
Can anyone help?? (10 Replies)
Discussion started by: vikashtulsiyan
10 Replies
4. Shell Programming and Scripting
Doubt regarding using "exec" command to redirect the STDERR to a file. e.g I did it this way.
mystage.sh
#!/bin/sh exec 2>stage.err
....
....
cat stage.err
mv: cannot move `/root/stage' to a subdirectory of itself, `/root/stage_old/stage'
ls: *.zDB: No such file or... (0 Replies)
Discussion started by: snurani
0 Replies
5. Shell Programming and Scripting
I dont know what I am doing wrong but I would like to redirect the stderr output to a file?
the specific command is this
time wget http://www.something.com/somefile.bin
All I want to see is time's output which is stderr so I can see how long the file download took. I've tried redirecting... (2 Replies)
Discussion started by: trey85stang
2 Replies
6. Shell Programming and Scripting
I am trying to redirect the output from stderr to a log file from within a bash script. the script is to long to add 2> $logfile to the end of each command. I have been trying to do it with the command exec 2> $logfile This mostly works. Unfortunately, when a read command requires that anything be... (5 Replies)
Discussion started by: vockleya
5 Replies
7. Shell Programming and Scripting
I'm not a complete novice at unix but I'm not all that advanced either. I'm hoping that someone with a little more knowledge than myself has the answer I'm looking for.
I'm writing a wrapper script that will be passed user commands from the cron...
Ex:
./mywrapper.sh "/usr/bin/ps -ef |... (1 Reply)
Discussion started by: sumgi
1 Replies
8. Shell Programming and Scripting
Hi,
I already searched through the forum and tried to find a answer for my problem but I didn't found a full working solution, thats way I start this new thread and hope, some can help out.
I wonder that I'm not able to find a working solution for the following scenario:
Working in bash I... (8 Replies)
Discussion started by: Boemm
8 Replies
9. Shell Programming and Scripting
Hi folks
I need/want to redirect output (stdout, stderr) from an exec call to separate files. One for stderr only and two(!) different (!) ones for the combined output of stderr and stdout.
After some research and testing i got this so far :
(( exec ${command} ${command_parameters} 3>&1... (6 Replies)
Discussion started by: MDominok
6 Replies
10. UNIX for Beginners Questions & Answers
I know that
mmmmm 2> error.txt
will send the error message to the specified file instead of the screen. However, I have seen
>&2
in some scripts, and I can't get it to do anything. A source said it sends stdout and stderr to a file. What file?
Ubuntu 18.04.2; Xfce 4.12.3;... (11 Replies)
Discussion started by: Xubuntu56
11 Replies
LEARN ABOUT NETBSD
filemon
FILEMON(4) BSD Kernel Interfaces Manual FILEMON(4)
NAME
filemon -- track interesting system calls
SYNOPSIS
#include <filemon.h>
DESCRIPTION
filemon provides a means for tracking the successful system calls performed by a process. It is used by make(1) to track the activities of
build scripts, for the purpose of automatically learning dependencies.
The data captured by filemon for the script
n=`wc -l /etc/motd`; echo "int motd_lines = $n;" > foo.h.new
cmp -s foo.h foo.h.new 2> /dev/null || mv foo.h.new foo.h
looks like:
# filemon version 4
# Target pid 24291
V 4
E 29676 /bin/sh
R 29676 /etc/ld.so.conf
R 29676 /lib/libedit.so.2
R 29676 /lib/libtermcap.so.0
R 29676 /lib/libc.so.12
F 29676 4899
E 4899 /usr/bin/wc
R 4899 /etc/ld.so.conf
R 4899 /usr/lib/libc.so.12
R 4899 /etc/motd
X 4899 0
W 29676 foo.h.new
X 29676 0
# Bye bye
E 3250 /bin/sh
R 3250 /etc/ld.so.conf
R 3250 /lib/libedit.so.2
R 3250 /lib/libtermcap.so.0
R 3250 /lib/libc.so.12
W 26673 /dev/null
E 26673 /usr/bin/cmp
R 26673 /etc/ld.so.conf
R 26673 /usr/lib/libc.so.12
X 26673 2
E 576 /bin/mv
R 576 /etc/ld.so.conf
R 576 /lib/libc.so.12
M 576 'foo.h.new' 'foo.h'
X 576 0
X 3250 0
# Bye bye
Most records follow the format:
type pid data
where type is one of the list below, and unless otherwise specified, data is a pathname.
C chdir(2).
D unlink(2).
E exec(3).
F fork(2), vfork(2); data is the process id of the child.
L link(2), symlink(2); data is two pathnames.
M rename(2); data is two pathnames.
R open(2) for read or read-write.
W open(2) for writing or read-write.
X exit(3); data is the exit status.
V indicates the version of filemon.
FILES
/dev/filemon
EXAMPLES
The following example demonstrates the basic usage of filemon:
#include <filemon.h>
pid_d pid;
int fd, tfd;
int status;
filemon_fd = open("/dev/filemon", O_RDWR);
temp_fd = mkstemp("/tmp/filemon.XXXXXXX");
/* give filemon the temp file to use */
ioctl(filemon_fd, FILEMON_SET_FD, &temp_fd);
/* children do not need these once they exec */
fcntl(filemon_fd, F_SETFD, 1);
fcntl(temp_fd, F_SETFD, 1);
pid = fork();
switch(pid) {
case -1:
err(1, "cannot fork");
break;
case 0:
pid = getpid();
/* tell filemon to monitor this process */
ioctl(filemon_fd, FILEMON_SET_PID, &pid);
execvp(...);
_exit(1);
break;
default:
status = wait();
close(filemon_fd);
lseek(temp_fd, SEEK_SET, 0);
/* read the captured syscalls from temp_fd */
close(temp_fd);
break;
}
The output of filemon is intended to be simple to parse. It is possible to achieve almost equivalent results with dtrace(1) though on many
systems this requires elevated privileges. Also, ktrace(1) can capture similar data, but records failed system calls as well as successful,
and is thus more complex to post-process.
HISTORY
filemon was contributed by Juniper Networks.
BSD
September 29, 2011 BSD