background functions doesn't display their output


 
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# 1  
Old 10-20-2009
background functions doesn't display their output

hello there,

there's a function, in my shell script, i'd like to run in the background.

here's an example:
Code:
log()
{
    local SELF=${0##*/}
    tty -s && echo "[$SELF]: $*"
}

some_func()
{
    # do something
    log "This text is not displayed in the terminal's output when running in the background"
}

some_func &
some_func &

# here's a code to wait these functions are complited

So, the problem is when I call these function in parallel I don't see any logs.

thanks
# 2  
Old 10-20-2009
The concept of running a function in background is not really defined as far as I know. By definition, a function is interpreted by the shell containing it's definition. A background command is executed by forking the shell and letting the subshell execute the command. So a shell can't background itself and execute a function at the same time.

Having said that, it's interesting that no error message is produced.... It may be that a subshell was created but the function doesn't exist because it's definition is not exported...
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