单项选择题
A. export LD_PRELOAD=/usr/local/lib
B. export LD_LIBRARY_PATH=/usr/local/lib
C. Idconfig /usr/local/lib
D. Idd/usr/local/lib
单项选择题 Usingvi，youwanttosavechangestothefilemyfilewith：w!，butvicomplainsitcannotwritetothefile.Therefore，youwanttocheckthewritepermissionsonthefile.Todothiswithoutleavingvi，youtype：（）
单项选择题 YouwishtokillaprocesswithaPIDof123.Selectthecommandwhichexiting.（）
单项选择题 WhichofthefollowingcommandswillchangeallCR-LFpairsinanimportedtextfile，userlist.txt，toLinuxstandardLFcharactersandstoreitasnewlist.txt？（）