c,bash,shell,gcc , How to deal with “warning: ignoring return value of ‘system’, ”


How to deal with “warning: ignoring return value of ‘system’, ”

Question:

Tag: c,bash,shell,gcc

I need to run some bash shell commands when my c program reaches to a certain point. What I have found by googling is that system() provides such a functionality. However, compiling the code by gcc generates a warning message like below and the bash command does not get executed. Any solution or alternative?

warning: ignoring return value of ‘system’, declared with attribute warn_unused_result [-Wunused-result]
system(command);

Answer:

It's a library call, and you are ignoring the return value from it, thats why that compiler warning. Assign it to a variable, check the return value (See man page of system). And that warning has nothing to do with your bash command not getting executed.


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