Re^4: Offset Reading

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Re^5: Offset Reading - two files by BrowserUk (Patriarch) on Dec 14, 2012 at 15:10 UTC
seek does not take a length (`$2` as its third parameter. If you changed that to: `perl -sple"BEGIN{open BIG};($1,$2)=split;seek(BIG,$1,$2);read(BIG,$_,0 +)" -- -BIG=bigfile.dat index.dat >outfile.dat` [download] It might work. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.	[reply] [d/l] [select]
Re^6: Offset Reading - two files by gio001 (Acolyte) on Dec 14, 2012 at 15:46 UTC
I have tried: `perl -sple 'BEGIN{open BIG};($1,$2)=split;seek(BIG,$1,0);read(BIG,$_,$2)' -- -BIG=bigfile.dat index.dat >outfile.dat` and I received the following: `Modification of a read-only value attempted at -e line 1, <> line 1` Thanks,	[reply] [d/l] [select]
Re^7: Offset Reading - two files by BrowserUk (Patriarch) on Dec 14, 2012 at 16:04 UTC
This seems to work: `C:\test>type junk.dat a_12_3_5- k_3_4_6-a_12_3_5- q_1_5_7_9- q_1_5_7_9- a_9_4_5-c_3_4_6- c_3_4_6-r_4_5_7- b_1_1_3- v_1_5_7- d_12_4_5-e_4_5_6- g_5_6_7-d_6_8_6- b_1_1_7-f_3_8_7_8-d_4_1_4- d_4_1_5-b_1_1_7-f_3_8_3 b_1_1_7-f_3_8_7_8-d_4_1_4- e_3_3_1-f_3_8_7-f_21_3_1-b_1_1_7-a_1_1_1- C:\test>perl -swple"BEGIN{open BIG};($o,$s)=split;seek(BIG,$o,0);read( +BIG,$_,$s)" -- -BIG=junk.dat con >junk2.dat 1 10 20 10 5 10 30 20 ^Z C:\test>type junk2.dat _12_3_5- k 12_3_5- q_ 3_5- k_3_4 _1_5_7_9- q_1_5_7_9-` [download] I leave it to you to work out why yours doesn't. With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday' Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error. "Science is about questioning the status quo. Questioning authority". In the absence of evidence, opinion is indistinguishable from prejudice. RIP Neil Armstrong	[reply] [d/l]
Re^8: Offset Reading - two files by gio001 (Acolyte) on Dec 14, 2012 at 16:14 UTC
Re^9: Offset Reading - two files by BrowserUk (Patriarch) on Dec 14, 2012 at 16:47 UTC
Some notes below your chosen depth have not been shown here
Re^8: Offset Reading - two files by gio001 (Acolyte) on Dec 14, 2012 at 17:22 UTC
Re^7: Offset Reading - two files by johngg (Canon) on Dec 14, 2012 at 16:11 UTC
You are trying to assign to `$1` and `$2` but these are special variables that are only set by successful regular expression match captures and are read-only otherwise (see Extracting matches). Use normal scalar variables with names that are something meaningful, like `$offset` and `$reclen` perhaps. I hope this is helpful. Cheers, JohnGG	[reply] [d/l] [select]
Re^7: Offset Reading - two files by Anonymous Monk on Dec 14, 2012 at 16:04 UTC
use splain or diagnostics to get more verbose error message Read about the variable you're using with `perldoc -v '$1'` and stop that :)	[reply]