Microsoft Word - LAB3.DOC

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3 *R WR \RXU KRPH GLUHFWRU\ 1R PDWWHU ZKHUH \RX DUH LW LV DOZD\V SRVVLEOH WR JR WR \RXU RULJLQDO KRPH GLUHFWRU\E\XVLQJ D VLPSOH FRPPDQG,I \RX W\SH cd ~ DQG WKHQ \RX VKRXOG VHH WKLV pegasus.montclair.edu% cd ~ /home/students/yourname 7KLV PHWKRG LV YHU\IDVW HVSHFLDOO\LI \RX DUH GHHS LQVLGH RI DQRWKHU GLUHFWRU\ 3ULQW WKH IXOO QDPH RI WKH FXUUHQW GLUHFWRU\,I \RX IRUJHW ZKHUH \RX DUH ORFDWHG LQ D GLUHFWRU\ VWUXFWXUH LW LV SRVVLEOH WR GLVSOD\WKH IXOO SDWK,I \RX W\SH \RX VKRXOG VHH WKLV pegasus.montclair.edu% /home/students/yourname 7KLV FRPPDQG LV FDOOHG SUHVHQW ZRUNLQJ GLUHFWRU\ 5HPRYH ILOHV XWLOL]H WKH ZLOG FDUG )URP WLPH WR WLPH \RXU GLUHFWRU\PD\JHW FOXWWHUHG ZLWK ILOHV DQG \RX PD\ FKRRVH WR GHOHWH WKHP,Q 0LFURVRIW :LQGRZV LW LV SRVVLEOH WR GUDJ WKLQJV WR WKH µuhf\foh ELQ RU RQ D 0DFLQWRVK WKLQJV PXVW EH VHQW WR WKH µwudvk,q 81,; WKHUH LV QRWKLQJ OLNH WKDW EXW WKHUH LV D FRPPDQG,I \RX W\SH rm HelloWorld.class DQG WKHQ y DQG WKHQ \RX VKRXOG VHH WKLV pegasus.montclair.edu% rm HelloWorld.class rm: remove HelloWorld.class (yes/no)? y &ODVV ILOHV DUH QRW QHFHVVDU\ WR NHHS DQ\WLPH \RX UXQ WKH MDYDF FRPPDQG D QHZ RQH ZLOO EH FUHDWHG )URP WLPH WR WLPH \RX VKRXOG GHOHWH WKHVH ILOHV,W LV DOVR SRVVLEOH WR GHOHWH PXOWLSOH ILOHV DW RQFH XVLQJ ZKDW LV FDOOHG D µzlog FDUG

4 ,I \RX W\SH rm *.class DQG WKHQ \RX VKRXOG VHH WKLV pegasus.montclair.edu% rm *.class No match %H YHU\ FDUHIXO XVLQJ WKLV LW GRHV QRW SURPSW \RX IRU D \HV RU D QR 2QO\ XVH WKLV WR JHW ULG RI.class ILOHV,Q DGGLWLRQ WR GHOHWLQJ WKLQJV WKH ZLOG FDUG * FDQ EH XVHG IRU RWKHU SXUSRVHV DV ZHOO 7KH EDVLF LGHD LV WKDW WKH * FDQ UHSODFH DQ\OHWWHU RU OHWWHUV \RX ZLVK WR RPLW 5HPRYH D GLUHFWRU\ 'LUHFWRULHV PXVW EH UHPRYHG IURP WKH V\VWHP LQ D VSHFLDO ZD\ WKH UP FRPPDQG ZLOO QRW ZRUN,I \RX W\SH rm temp DQG WKHQ \RX VKRXOG VHH WKLV pegasus.montclair.edu% rm temp %HIRUH \RX FDQ GHOHWH D GLUHFWRU\ LW PXVW EH HPSW\,I \RX KDSSHQ WR JHW DQ HUURU PHVVDJH EH VXUH WR FKHFN DQG VHH LI WKH GLUHFWRU\LV HPSW\ 'LVSOD\ D ILOH ZLWKRXW XVLQJ D WH[W HGLWRU /DVWO\ LW LV SRVVLEOH WR YLHZ D ILOH RU ILOHV ZLWKRXW RSHQLQJ DQ HGLWRU OLNH QHGLW 7KHUH DUH VHYHUDO ZD\V WR GR WKLV, DP JRLQJ WR KLJK OLJKW WZR RI WKHP,I \RX W\SH cat HelloWorld.java \RX VKRXOG VHH WKLV pegasus.montclair.edu% cat HelloWorld.java // File name: HelloWorld.java // Author: Yourname // Date: January 23, 2003 public class HelloWorld public static void main (String[] args) System.out.println ("Hello World!"); 7KH FRPPDQG cat VWDQGV IRU FRQFDWHQDWH WKH UHDO XVH RI WKLV ILOH LV WR FRPELQH ILOHV WRJHWKHU EXW LW ZRUNV ZHOO IRU GLVSOD\LQJ WKH FRQWHQWV RI D ILOH DV ZHOO

5 ,I \RX W\SH more HelloWorld.java \RX VKRXOG VHH WKLV pegasus.montclair.edu% more HelloWorld.java // File name: HelloWorld.java // Author: Your name // Date: January 23, 2003 public class HelloWorld public static void main (String[] args) System.out.println ("Hello World!"); 7R +DQG LQ 7KH FRPPDQG PRUH LV XVHIXO IRU YLHZLQJ ODUJH ILOHV $IWHU SULQWLQJ RQH VFUHHQ LW ZLOO SDXVH XQWLO WKH VSDFH EDU LV SUHVVHG 7KLV ZD\LW LV SRVVLEOH WR UHDG D GRFXPHQW DW \RXU RZQ SDFH,I \RX KDYHQ W SULQWHG \RXU DVVLJQPHQW IURP ODVW ZHHN ODEW[W \RX VKRXOG GR VR QRZ lpr PRI108H lab2.txt 'R WKH IROORZLQJ FRPPDQGV H[DFWO\DV WKH\DSSHDU cd ~ akscript lab3.txt mk lab3 cd lab3 mk child cd child cd.. rm child cd.. rm lab3 cat lab2.txt exit lpr PRI108H lab3.txt Remark: For more UNIX commands check the UNIX Reference on the Information part on the syllabus.