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RHEL/Centos7 Shell tips: bc/printf

 1. BC

[email protected]:~/tmp$ bc
bc 1.06.95
Copyright 1991-1994, 1997, 1998, 2000, 2004, 2006 Free Software Foundation, Inc.
This is free software with ABSOLUTELY NO WARRANTY.
For details type `warranty'. 
 
ibase   <<<<<<<< default dec for input
10
obase  <<<<<<<< default dec for output
10
ibase=16   <<< change input to hex
obase=2  <<< change output to binary 
55    <<<< input 0x55/hex mode
1010101    <<<< output of binary for input 0x55

2. printf
[email protected]:~/tmp$ which printf
/usr/bin/printf
[email protected]:~/tmp$ file    /usr/bin/printf
/usr/bin/printf: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=318c48d6d29df539048faaeb48cb65c98722d0e4, stripped

[email protected]:~/tmp$ printf "%d\n"  "'3'"
51