查看命令行提供的参数
#include <stdio.h> int main(int argc, char *argv[]) { int count; printf("The command line has %d arguments:\n", argc); for(count = 0; count < argc; count++) printf("%d: %s\n", count, argv[count]); return 0; }
一个实用的文件复制程序
#include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { FILE *fpin, *fpout; if( argc < 3) { printf("you must provide the source and target file.\n"); exit(0); } if((fpin = fopen(argv[1], "r"))==NULL) { printf("the source file open fail.\n"); exit(0); } if((fpout = fopen(argv[2], "w"))==NULL) { printf("the targe file open fail.\n"); exit(0); } char ch; while((ch=getc(fpin))!=EOF) putc(ch, fpout); printf("The file is copied.\n"); fclose(fpout); fclose(fpin); return 0; }