print ascii art of text
ex. banner -c x text
print "text" with x characters like below
xxxxxxx
x x x x
x x
x xxxxx xxx xxx xxxx
x x x x x x
x xxxxxxx xxx x
x x xxx x
x x x x x x x
xxx xxxxx xxx xxx xx
compare 2 files byte by byte
ex. cmp filea fileb
colored version of diff tool TODO:
split a file into pieces
ex. split -b 3 original_file
split original_file into xaa, xab, xac, ... and cat makes pieces into a file
cat * > combined_file
split a file into pieces determined by patterns
ex. split original_file '/[0-9]*0:/' '{*}'
split a file into pieces by line number: line starts with "00:" ~ "09:" -> xx00 "10:" ~ "19:" -> xx01 "20:" ~ "29:" -> xx02 ... cat can be also used for the reverse operation
cat * > combined_file
convert and copy a file TODO:
display file status
ex. stat -c %s somefile
output file size of somefile
shrink or extend the size of file to the specified size
ex. truncate -s 1024 somefile
extend the size of somefile to 1024 bytes.
make temp file and output its name TODO:
displays descriptions of commands, functions, or system calls
ex. whatis -w "*print*"
displays the descriptions of the commands which name contains "print".
ex. whatis -s1 printf
displays the description of the command "printf", not the c function. section 1 of man pages contain manual about executable programs or shell commands. you can "man man" for further information of the sections.
this is reverse version of whatis. search commands, functions, or system calls by keyword.
ex. apropos -s1 calc
encode/decode base64
print 16-bit checksum
print CRC checksum
compute and check MD5 message digest
ex. md5sum -c somefile.md5
check MD5 of the files described in somefile.md5
ex. md5sum somefile > somefile.md5
print MD5 checksum to somefile.md5
dump the code sent by the keyboard (in zsh) Ctrl-V + <some key> makes the same effect.
convert tabs to spaces and do the reverse
ex. expand -t 4 file_with_tab > file_with_space
convert tabs to 4 spaces
ex. unexpand -t 4 file_with_space > file_with_tab
convert 4 spaces to tabs
output a string repeatedly until killed
ex. yes | sh install.sh
answer 'y' to all questions install.sh asks.
ends with status true/false
ex. true
exit with 0
ex. false
exit with 1
display lines beginning with a given string
ex. look "Result:" somelog
find line beginning with "Results" in somelog.
join lines of 2 files on a common field
ex. join -a 2 -j 1 filea fileb
join lines of filea and fileb on a field 1. (space separated fields)
print files in reverse
ex. echo "abc\ncde\n" | tac
this outputs like below
cde
abc
print reverse lines of files
ex. echo "abc\ncde\n" | rev
this outputs like below
cba
edc
converts text from one encoding to another
ex. iconv -f utf-8 -t sjis somefile > somefile_sjis
converts encoding of somefile from utf-8 to sjis
wrap each line to fit in specified width
ex. someprg | fold -w 50
wrap each line of someprg output to fit in 50 width
merge lines of files
ex. echo "ab\ncd" > filea && echo "ef\ngh" > fileb && paste filea fileb
merge lines of filea and fileb like below
ab ef
cd gh
TODO:
show calendar
advanced calculator
ex. calc "base(16), 1 + 0xf0"
output 1 + 0xf0 result in hex web site is located at http://www.isthe.com/chongo/tech/comp/calc/
print shared library dependencies
print user's login name
print the user names of users currently logged in.
print the groups a user is in.
TODO:
TODO:
TODO:
monitor network bandwidth
monitor file i/o
network diagnosis tool
ex. mtr 192.168.0.3
schedule batch job
ex. at 1130
schedule command to execute at 11:30 of the day
TODO:
sleep for a specified amount of time
ex. sleep 10s
sleep 10 seconds
parse command options TODO:
TODO:
password generator
ex. apg -q -m 8 -x 8 -M NC -t
generate password with length 8. password consists of numbers and characters.
tty recorder and player like script
xml well formed checker TODO:
xml advanced checker TODO:
generate navigation tags file for source code
ex. ctags -R
create tags file for source codes by descending directory
bash script debugger
ex. bashdb test.sh 1 2 3
start debugger for test.sh (args=1 2 3)
trace the system calls and signals TODO:
copy and translate object files
get source line number of addr
ex. addr2line -e someprg 0x00401040
ex. addr2line -e someprg -j .text 0x00000040
make a hexdump or do the reverse
ex. xxd somefile
output a hexdump of somefile
discard symbols from object files.
ex. strip someprg
discard symbol information from someprg.
list section sizes
ex. size someprg
list section sizes of someprg
list string from object files TODO: