Whats the best way to read in a very large amount of data from an external program

Pipes! See for example perlopentut for some piping examples.

I think not and AFAIK the only way to do this would be to modify the nfdump command to pause execution when blocked by my program (or use files but I prefer not to really). I wonder if its possible to block execution of the external program without modifying it.

Writing to a pipe whose buffer size is exceeded does in fact block, so unless the program that writes stuff takes special care to do non-blocking writes, pipes already do what you want.

Isn't that wonderful?

Perl 6 - the future is here, just unevenly distributed

In reply to Re: Blocking execution of called programs to reduce buffer size by moritz
in thread Blocking execution of called programs to reduce buffer size by Peterpion

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