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Mail Archives: djgpp/2000/09/23/15:00:12

Message-ID: <39CCF175.275438D7@netzero.net>
From: "Kenneth A. Strom" <therelic AT netzero DOT net>
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Newsgroups: comp.os.msdos.djgpp
Subject: Re: Extract a value from a string?
References: <39CABE68 DOT D5AA584B AT netzero DOT net> <969595461 DOT 718378 AT shelley DOT paradise DOT net DOT nz> <i35z5.4837$8X6 DOT 4960 AT newsfeed DOT slurp DOT net>
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To: djgpp AT delorie DOT com
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If the string is...

Capture = 0

Would it be better to strstr for = and then extract from the position
of  = + 1 into another string and then atoi?  Does atoi handle
whitespace?

Or should I search for the first number digit (0-9) and extract from
there to the end and atoi?

Ken.
therelic AT netzero DOT net

bowman wrote:

> Edmund Horner <ejrh AT paradise DOT net DOT nz> wrote in message
> news:969595461 DOT 718378 AT shelley DOT paradise DOT net DOT nz...
> > char *str;   // this is the string.
> > int n;
> > n = atoi (str);   // method 1.
> > sscans (str, "%d", &n);   // method 2.
>
> couple of minor points:
> using strtol() instead of atoi allow you to test if the string
> was actually a valid number, as well as allowing a base
> to be specified.
>
> checking the return from sscanf() will verify that a numeric
> string was actually found, converted, and placed in 'n'
>
> otherwise, atoi will happily return 0 on a bogus string and
> sscanf() will leave n as garbage.

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