How to specify an optstring in the getopt function?

c getopt
bLAZ picture bLAZ · Nov 6, 2012 · Viewed 20.9k times · Source

I'm not sure how to correctly use optstring in the getopt function in C.

How should that string be formatted? I saw examples where letters are next to each other, sometimes separated by a semicolon, sometimes by two semicolons.

What does it mean?

Answer

md5 picture md5 · Nov 6, 2012

It is just a string, and each character of this string represents an option. If this option requires an argument, you have to follow the option character by :.

For example, "cdf:g" accepts the options c, d, f, and g; f requires an additional argument.

An option in command line looks like -option, so you can use the options -c, -d, -f argument and -g.

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