请教编程！
// example of macro to read data from an ascii file and// create a root file with a Tree.
// see also a variant in cernbuild.C
// Author: Rene Brun
void staff() {
struct staff_t {
Int_t Category;
UInt_t Flag;
Int_t Age;
Int_t Service;
Int_t Children;
Int_t Grade;
Int_t Step;
Int_t Hrweek;
Int_t Cost;
Char_t Division;
Char_t Nation;
};
staff_t staff;
//The input file cern.dat is a copy of the CERN staff data base
//from 1988
FILE *fp = fopen("cernstaff.dat","r");
char line;
TFile *f = new TFile("staff.root","RECREATE");
TTree *tree = new TTree("T","staff data from ascii file");
tree->Branch("staff",&staff.Category,"Category/I:Flag:Age:Service:Children:Grade:Step:Hrweek:Cost");
tree->Branch("Division",staff.Division,"Division/C");
tree->Branch("Nation",staff.Nation,"Nation/C");
//note that the branches Division and Nation cannot be on the first branch
while (fgets(&line,80,fp)) {
sscanf(&line,"%d %d %d %d %d",&staff.Category,&staff.Flag,&staff.Age,&staff.Service,&staff.Children);
sscanf(&line,"%d %d %d %d %s %s",&staff.Grade,&staff.Step,&staff.Hrweek,&staff.Cost,staff.Division,staff.Nation);
tree->Fill();
}
tree->Print();
tree->Write();
fclose(fp);
delete tree;
delete f;
}
在程序中 char line;定义了一个字符数组，长度为80
程序
while (fgets(&line,80,fp)) {
sscanf(&line,"%d %d %d %d %d",&staff.Category,&staff.Flag,&staff.Age,&staff.Service,&staff.Children);
sscanf(&line,"%d %d %d %d %s %s",&staff.Grade,&staff.Step,&staff.Hrweek,&staff.Cost,staff.Division,staff.Nation);
tree->Fill();
}
中
1。while (fgets(&line,80,fp))意思是什么？
2。 sscanf(&line,"%d %d %d %d %d",&staff.Category,&staff.Flag,&staff.Age,&staff.Service,&staff.Children);
中的&line更是不明白了？请问是什么意思？
3。sscanf(&line,"%d %d %d %d %s %s",&staff.Grade,&staff.Step,&staff.Hrweek,&staff.Cost,staff.Division,staff.Nation);
中的&line同样不明白，请问是什么意思？
谢谢phenixwutao！ C还是SHELL？ 找本C语言基础知识看看，呵呵还有CPP呢。这个问题不是几下可以说清楚的。
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