Monthly Archives: June 2011

id – print real and effective user and group IDs

A UNIX Command $id uid=1000(jeffrin) gid=1000(jeffrin) groups=1000(jeffrin),29(audio),1001(wireshark) $id -n id: cannot print only names or real IDs in default format $id -a uid=1000(jeffrin) gid=1000(jeffrin) groups=1000(jeffrin),29(audio),1001(wireshark) $id -g 1000 $id -G 1000 29 1001 $id -Gn jeffrin audio wireshark $id -r id: cannot print only names or real IDs in default format $id -rG 1000 29 …

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logname – print user´s login name

A UNIX Command $logname jeffrin $logname –help Usage: logname [OPTION] Print the name of the current user. –help display this help and exit –version output version information and exit Report logname bugs to bug-coreutils@gnu.org GNU coreutils home page: General help using GNU software: For complete documentation, run: info coreutils ‘logname invocation’ $logname –version logname (GNU …

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csplit – split a file into sections determined by context lines

A UNIX Command $cat test.text hello how are you ? $csplit test.text 1 0 20 $cat xx00 $cat xx01 hello how are you ? $rm xx* $csplit test.text 2 6 14 $cat xx00 hello $cat xx01 how are you ? $rm xx* $csplit test.text 3 10 10 $cat xx01 are you ? $cat xx00 hello …

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truncate – shrink or extend the size of a file to the specified size

A UNIX Command $cat example.text hello $ls -l example.text -rw-r–r– 1 jeffrin jeffrin 6 Jun 21 02:32 example.text $truncate -s 10 example.text $ls -l example.text -rw-r–r– 1 jeffrin jeffrin 10 Jun 21 02:35 example.text $hexdump example.text 0000000 6568 6c6c 0a6f 0000 0000 000000a $cat example.text hello $truncate -s 9 example.text $ls -l example.text -rw-r–r– 1 …

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xwd – dump an image of an X window

A UNIX Command $xwd -out ldump $du -h ldump 1.4M ldump $hexdump -n 1 ldump 0000000 0000 0000001 $hexdump -n 5 ldump 0000000 0000 7600 0000 0000005 $hexdump -n 10 ldump 0000000 0000 7600 0000 0700 0000 000000a $hexdump -n 50 ldump 0000000 0000 7600 0000 0700 0000 0200 0000 1000 0000010 0000 0004 0000 …

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