in reply to detect input available from command line

if ( @ARGV ) {
    while (<>) {
    }
}
else {
    # do something else
}

[download]

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Re^2: detect input available from command line
by mifflin (Curate) on Mar 10, 2011 at 21:51 UTC
    What if the input is not coming from @ARGV but from stdin?
    example: 
    $ ./testprog -t testing@testing.com -s test5 <<EOT;
> stuff
> typed
> in 
> here
> EOT

    [download]
    In this case @ARGV is empty but there is still something to read. How would I detect this?
[reply]
[d/l]

      You could test 

      if (@ARGV or !-t STDIN and !eof()) {
    while (<>) {
        ...

      [download]

      (but any non-input file arguments would need to be removed from @ARGV first, of course)

      This should work with input file arguments on the command line, heredoc input (<<), input redirect (<), and piping into the program (|).

      Update: actually, I think you don't even need the eof().

[reply]
[d/l]
[select]

      I have a program that may try to get data from the command line using

      What if the input is not coming from @ARGV but from stdin?

      If the input is coming from STDIN then it is not on the command line.

[reply]

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