How to find out the length of the string?

I define a string:
string line;

I read the string from a file:
ifstream fin("abc.txt");
while (getline(fin,line)) {

I check for keyword "Failed" at position 78
if (line.substr(78,6) == "Failed") {


Now, the problem: sometimes, the string is shorter than 78 characters, and the program aborted.

Please tell me how to find out the string length. I tried strlen, but strlen can only be used for string character.

Please show me your script.

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Hi ccjong,
line.size() would give u the lenngth


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Just to add to Sys_Prog,

You can modify your condition statement so it first checks the size before checking substr.
If size condition fails, it will not check substr condition.
if (line.size() > 98 &&line.substr(78,6) == "Failed") {
//78+6=84 (so size should be at least 84)
if (line.size() > 83 && line.substr(78,6) == "Failed") {
ccjongAuthor Commented:
Thanks everyone.
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