How to pass command line parameters from a file

linux pipe command-line-arguments cat argv
Jonatas Eduardo picture Jonatas Eduardo · Jul 5, 2011 · Viewed 10.3k times · Source

I have a C program that reads command line arguments from argv. Is it possible to make a pipe to redirect the contents of a file as command line arguments to my program? Suppose I have a file arguments.dat with this content:

0 0.2 302 0

And I want my program to be called with:

./myprogram 0 0.2 302 0

I tried the following:

cat arguments.dat | ./myprogram

without success.

Answer

Kerrek SB picture Kerrek SB · Jul 5, 2011

xargs is your answer:

cat arguments.dat | xargs ./myprogram

Or easier:

xargs -a arguments.dat ./myprogram

Check the manual for the many ways to customize xargs. For example, you can read line-by-line rather than by word, and you can use the arguments in more complex replacements.

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