I think , in g() function , when ${1} fd goes to background ,f() function process at once,after then pipe is missing for that created 63fd..
therefore `/dev/fd/63` fd can not found by the g function.so g() function can not call f() function via same fd at the same time..
maybe you can try like this
Code:
..............
g() {
exec 4<${1}
f 1 <${1} &
f 2 <&4
}
...............
.........
regards
ygemici
You wouldn't want exec there. Better would be to put the redirect after the function definition. Yours is essentially equivalent to the example before it.
Anyway my question was mostly answered on the Bash mailing list.
POSIX says that background processes are always supposed to implicitly have their stdin redirected to /dev/null. Bash for some reason only sometimes follows this, and the pipe somehow affects whether that happens. The background processes shouldn't ever be getting input unless stdin is explicitly redirected. The 5th example from an updated version of the above shows another strange behavior where stdin of a list is determined by any redirects in the list.
How do you capture the return code from a background process?
I am dumping data to a fifo and then processing it in a c program.
I need to know that the sql finished successfully to ensure no missing data. Thanks.
ex.
sqlplus user/password < get_data.sql > data_fifo.txt &
bin/process_data... (2 Replies)
hi there,
here's what i need in my korn-shell:
... begin korn-shell script
... nohup process_A.ksh ; nohup process_B.ksh &
... "other stuff"
... end lorn-shell script
in plain english i want process A and process B to run in the background so that the script can continue doing... (6 Replies)
Hey guys,
I am writing a very simple dummy shell in C++ and I am having trouble getting a process to run in the background. First of all, the shell has to recognize when I input a "&" at the end of the command, then it has to stick it in the background of the shell.
I understand that if I want... (6 Replies)
Hi!
First of all, let me warn you I'm quite new to the world of LINUX and Operating Systems understanding, so that's why I pose these newbie and stupid qustions...
Anyway, I'm trying to build my own simple shell in C and I'm getting some problems in implementing the background process ('&')... (10 Replies)
I have installed oracle 10g on suse sles9. I do not see oracle background processes.
ps -ef|grep ora_ gives me environment variables junk.
ps -ef|grep smon does not show anything however database is up and running.
Any idea how to tweak that? (1 Reply)
Hi,
Inorder to improve the performance, I am trying to execute my command as a background process..
For eg: To zip large numbers of files present in a directory instead of using a single process, i do follow the below method:
gunzip -c > / &... (3 Replies)
Hi,
I need to establish a procedure that will start an application in background each time my remote Solaris server is (re)started. This would be a kind of daemon. I am no sysadmin expert, so I am looking for pointers.
How should I proceed? What are the main steps?
Thanks,
JVerstry (9 Replies)
Ok guys so I have my first dummy shell almost done except for one tiny part: I do not know how to run a process in the background, from the code!
I already know how to do that in a normal shell:
$ program &
However, no clue when it comes to how to program that thing. :eek:
A very... (2 Replies)
Hi,
I have a schell script parent.ksh from which I am calling three background processes a.ksh,b.ksh and c.ksh. Once these three processes completes the next step in parent.ksh should execute. How to achieve this?
Please help me....
Thanks... (1 Reply)
How do I list the process in a Unix based system which are running in background?
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b. using jobs -l, and filtering... (5 Replies)
Discussion started by: kumarjt
5 Replies
LEARN ABOUT REDHAT
set_color
set_color(1) fish set_color(1)NAME
set_color - set_color - set the terminal color
set_color - set the terminal color
Synopsis
set_color [-v --version] [-h --help] [-b --background COLOR] [COLOR]
Description
Change the foreground and/or background color of the terminal. COLOR is one of black, red, green, brown, yellow, blue, magenta, purple,
cyan, white and normal.
o -b, --background Set the background color
o -c, --print-colors Prints a list of all valid color names
o -h, --help Display help message and exit
o -o, --bold Set bold or extra bright mode
o -u, --underline Set underlined mode
o -v, --version Display version and exit
Calling set_color normal will set the terminal color to whatever is the default color of the terminal.
Some terminals use the --bold escape sequence to switch to a brighter color set. On such terminals, set_color white will result in a grey
font color, while set_color --bold white will result in a white font color.
Not all terminal emulators support all these features. This is not a bug in set_color but a missing feature in the terminal emulator.
set_color uses the terminfo database to look up how to change terminal colors on whatever terminal is in use. Some systems have old and
incomplete terminfo databases, and may lack color information for terminals that support it. Download and install the latest version of
ncurses and recompile fish against it in order to fix this issue.
Version 1.23.1 Sun Jan 8 2012 set_color(1)