?????? ?????д

?????????????
?????????
????д???
????ж??????
?塢?????в???
?????????

?????????????
 ???open (filevar, filename)??????filevar???????????????????????????????????????filename??????????·????????·????????????·????
 open(FILE1,"file1");
 open(FILE1, "/u/jqpublic/file1");
 ???????????????????????PERL???????????????????д????????????????????????д??????????????????????????????open(outfile,">outfile");??????????????????β????????????????????open(appendfile, ">>appendfile")???????????????????????ж???д/????????
 open????????????????????????????????????????????????????????????????????ж??
 if (open(MYFILE, "myfile")) {
 # here's what to do if the file opened successfully
 }
 ???????????????????
 unless (open (MYFILE, "file1")) {
 die ("cannot open input file file1\n");
 }
 ?????????????????????￡?
 open (MYFILE, "file1") || die ("Could not open file");
 ???????????????close(MYFILE); ????????
?????????
 ???$line = <MYFILE>;??????ж?????????洢????????$line?в?????????????????С?<STDIN>??????????????????????????????????
 ???@array = <MYFILE>;?????????????????????@array???????????(???????)?@array?????????
????д???
 ??????
 open(OUTFILE, ">outfile");
 print OUTFILE ("Here is an output line.\n");
 ???STDOUT??STDERR???????????????????????????????????????
????ж??????
1??????????????
 ?????-op expr???磺
 if (-e "/path/file1") {
 print STDERR ("File file1 exists.\n");
 }

????????????

??????	????
-b	???????豸
-c	????????豸
-d	??????
-e	??????
-f	??????????
-g	?????????setgidλ
-k	?????????stickyλ
-l	????????????
-o	?????и????
-p	???????
-r	?????
-s	?????
-t	????????
-u	?????????setuidλ
-w	????д
-x	???????
-z	?????????
-A	????η???????
-B	?????????????
-C	????η????????inode?????
-M	????????????
-O	???????????????????????
-R	?????С???????????????
-S	????socket
-T	??????????
-W	??????"?????????"??д
-X	??????"?????????"?????
??????????????????????????userid????????????ID????????suid????????Ч???ID??

????
 unless (open(INFILE, "infile")) {
 die ("Input file infile cannot be opened.\n");
 }
 if (-e "outfile") {
 die ("Output file outfile already exists.\n");
 }
 unless (open(OUTFILE, ">outfile")) {
 die ("Output file outfile cannot be opened.\n");
 }
 ?????
 open(INFILE, "infile") && !(-e "outfile") &&
 open(OUTFILE, ">outfile") || die("Cannot open files\n");
?塢?????в???
 ??C?????PERL??д洢?????в?????????@ARGV???????????????????????в???????C????????$ARGV[0]????????????????????????????
 $var = $ARGV[0]; # ?????????
 $numargs = @ARGV; # ?????????
 PERL?У?<>??????????????????@ARGV??????????????乤????????
1????PERL??????????ο???<>???????$ARGV[0]?????????????
2????ж???shift(@ARGV); ????????@ARGV??????????????????????????????????????
3??<>???????????????????????е??????С?
4??????????????????????????
 ????
 @ARGV = ("myfile1", "myfile2"); #????????????в??????
 while ($line = <>) {
 print ($line);
 }
 ???????myfile1??myfile2??????????????
?????????
 ?ó?????????????????????????????ù??(ex:ls > tempfile)???????open (MYPIPE, "| cat >hello"); ???????????????MYPIPE????????????"cat >hello"??????????cat???????????????????????????????open(MYPIPE, ">hello"); ?ù????????????￡?
 open (MESSAGE, "| mail dave");
 print MESSAGE ("Hi, Dave! Your Perl program sent this!\n");
 close (MESSAGE);

????? ????? Perl???

paper | appdir | ssv

这里只有精品视频