I have a C program that continously outputs info to stdout. The problem is that I am redirecting the stdout and stderr to a file and stdout is written at the end of the problem rather than continously to the file. This could be a problem if for example the program is killed and the stdout output is lost. On the other hand, stderr is written continuously to the file.
Thats the way I am doing the redirection of the stdout and stderr.
Any ideas how can I redirect the stdout to the file continuously rather than at the end of the program?
Last edited by methyl; 06-26-2012 at 06:40 PM..
Reason: please use code tags
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)
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)
Is there a way to redirect all stdout to a file implicitly - like defining stdout=/home/me/process.log - so that all "echo" commands in several scripts/subscripts are written to that file; instead of having to edit all scripts to redirect the "echo" (e.g. echo 'This is a test ' >>... (1 Reply)
I have an executable that, depending on its input, outputs to either one file or several. It usually prints nothing on screen. The usual way to call this program is to specify an input and output filenames, like this:
./executable.exe -i inputfile -o outputfileIt will then try to use the output... (1 Reply)
Hi everybody,
I am trying to do the thing you see in the title, and I can't simply do
a=$(svn up)
echo $a
because the program (svn) gives output on lots of lines and in the variable the output is stored on only one line (resulting in a horribly formatted text). Any tips?
Thanks,... (2 Replies)
Hello,
I have a script (videostream.sh) which invokes the GStreamer command-line tool gst-launch with all the correct command line parameters. When I invoke this program, I add the '&' character at the end to make it a background task, so that my script can complete and exit, i.e.
gst-launch... (1 Reply)
I have a simple bash script that prints sth every 5 seconds. What I do is the following. I redirect the output of the script to a file, tail the file and see that it works and then from another console I delete the file where the output is redirected to. Even though I have deleted the file, the... (2 Replies)
Hello all. I've been lurking here for a year or two and finally decided to post.
I need some assistance with file descriptors, stdout, and redirecting output. I've searched through a number of very helpful threads here (unfortunately I can't link to any of them yet due to my low post count...),... (2 Replies)
I have to redirect STDERR messages both to screen and also capture the same in a file but STDOUT only to the same file.
I have searched in this formum for a solution, but something like
srcipt 3>&1 >&2 2>&3 3>&- | tee errs
doesn't work for me...
Has anyone an idea??? (18 Replies)
Hello,
I'm strugling with some redirecting and all help is apreciated.
The following program is working as expected, but the result of the AT command doesn't go to any file.
Thanks in advance for the help.
#!/bin/bash
modem=/dev/ttyUSB1
file=/root/imsi.txt
# print error to stderr and exit... (4 Replies)
Discussion started by: cleitao
4 Replies
LEARN ABOUT NETBSD
atf-check
ATF-CHECK(1) BSD General Commands Manual ATF-CHECK(1)NAME
atf-check -- executes a command and analyzes its results
SYNOPSIS
atf-check [-s qual:value] [-o action:arg ...] [-e action:arg ...] [-x] command
atf-check -h
DESCRIPTION
atf-check executes a given command and analyzes its results, including exit code, stdout and stderr.
In the first synopsis form, atf-check will execute the provided command and apply checks specified by arguments. By default it will act as
if it was run with -s exit:0 -o empty -e empty. Multiple checks for the same output channel are allowed and, if specified, their results
will be combined as a logical and (meaning that the output must match all the provided checks).
In the second synopsis form, atf-check will print information about all supported options and their purpose.
The following options are available:
-h Shows a short summary of all available options and their purpose.
-s qual:value Analyzes termination status. Must be one of:
exit:<value> checks that the program exited cleanly and that its exit status is equal to value. The exit code can be omit-
ted altogether, in which case any clean exit is accepted.
ignore ignores the exit check.
signal:<value> checks that the program exited due to a signal and that the signal that terminated it is value. The signal
can be specified both as a number or as a name, or it can also be omitted altogether, in which case any signal
is accepted.
Most of these checkers can be prefixed by the 'not-' string, which effectively reverses the check.
-o action:arg Analyzes standard output. Must be one of:
empty checks that stdout is empty
ignore ignores stdout
file:<path> compares stdout with given file
inline:<value> compares stdout with inline value
match:<regexp> looks for a regular expression in stdout
save:<path> saves stdout to given file
Most of these checkers can be prefixed by the 'not-' string, which effectively reverses the check.
-e action:arg Analyzes standard error (syntax identical to above)
-x Executes command as a shell command line, executing it with the system shell defined by ATF_SHELL in atf-config(1). You
should avoid using this flag if at all possible to prevent shell quoting issues.
EXIT STATUS
atf-check exits 0 on success, and other (unspecified) value on failure.
EXAMPLES
# Exit code 0, nothing on stdout/stderr
atf-check 'true'
# Typical usage if failure is expected
atf-check -s not-exit:0 'false'
# Checking stdout/stderr
echo foobar >expout
atf-check -o file:expout -e inline:"xx yy
"
'echo foobar ; printf "xx yy
" >&2'
# Checking for a crash
atf-check -s signal:sigsegv my_program
# Combined checks
atf-check -o match:foo -o not-match:bar echo foo baz
SEE ALSO atf-config(1), atf(7)BSD June 27, 2010 BSD