Hola Monks...

I have some code like this: 

my $pid = open(SFTP, '|-', "sftp $hostname > /tmp/_sftplog.txt");

print SFTP "some commands";
        
close (SFTP);

my $pidflag;
        
do {
  system('sleep 5');
  $pidflag = `ps -a \| grep -c \' $pid \'`;
  chomp($pidflag);  
} while ($pidflag);

[download]
which checks via 'ps' to see if the spawned sFTP process has ended--that is, the grep count of its PID is 0--before moving on (the space is to make sure '1134' doesn't match '11134', etc.). I have two questions:

1) Is this even necessary? Does close() guarantee the process has finished?

2) Is there a less kludgy way to do this? My method seems very crude. I poked around at the $? variable, but it doesn't seem to give me what I want.

Thanks,

~evan

In reply to Waiting for an external process to end? by eweaverp

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