shell programming series 15-- awk printf formatted output of text processing trio printf format specifier specifier meanings % S print string % D print decimal number % F print a float % X print hexadecimal % O Print octal number % in the form of printed mathematical e scientific notation % C the ASCII code printing a single character printf modifiers modifier meaning- left + Right alignment # preceded displayed in octal 0, displayed in hexadecimal preceded 0x the printf awk output format of summary: specifier
% S print string % D 10 print decimal % F print float % X print hexadecimal %o Printing octal % E scientific notation numbers printed formats % C print a single character ASCII code modifier - Left + Right alignment # preceded displayed in octal 0, 0x, hexadecimal display in front of the format operator example: 1 , print string format / etc / passwd in the seventh field to " : " delimiter awk ' the BEGIN {the FS = ":"} {the printf "% S \ n-', $. 7} ' the passwd 2 , printed in decimal format / etc / passwd in the third field, to " : " delimiter awk ' the BEGIN {the FS = ":" {} the printf "% D \ n-', $}. 3 ' the passwd . 3 , floating-point format print / etc / passwd in the third field, to " :" As the delimiter awk ' the BEGIN {the FS =": "{} the printf"% 0.2f \ n-', $}. 3 ' the passwd . 4 , the print / etc / passwd in the third field in hexadecimal format to " : " as the separator awk ' the BEGIN {the FS =": "} {the printf"% X \ n-', $. 3} ' the passwd . 5 , the print / etc / passwd in the third field in octal format to " : " as the separator awk ' the BEGIN {the FS =": "} {the printf"% O \ n-', $. 3} ' the passwd . 6 , print in scientific notation format / etc / passwd in the third field, to " : " as a delimiter awk 'BEGIN{FS=":"}{printf "%e\n",$3}' passwd Example Modifier: 1 , left justified format - 2 , right aligned in the + 3 , print octal or hexadecimal numbers are preceded by # # the printf no default delimiter [the root @ localhost 5.11 ] # awk ' the BEGIN {the FS = ":"} {the printf $. 1} ' the passwd rootbindaemonadmlpsyncshutdownhaltmailoperatorgamesftpnobodysystemd - networkdbuspolkitdsshdpostfixajiechronydeploynginx # added wrap, formatted output [the root @ localhost 5.11 ] # awk ' the BEGIN {the FS = ":"} {the printf "% S \ n-", $. 1} ' passwd root bin daemon adm lp Sync the shutdown the HALT mail operator games FTP the nobody systemd - Network dbus polkitd the sshd postfix ajie the chrony Deploy Nginx # placeholder landscaping output, the default is right justified [the root @ localhost 5.11 ] # awk ' the BEGIN {the FS = ":" {} the printf "% 20S% 20S \ n-",. 1 $, $}. 7 ' / etc / the passwd the root / bin / the bash bin / sbin / nologin daemon / sbin / nologin ADM / sbin /nologin lp /sbin/nologin sync /bin/sync shutdown /sbin/shutdown halt /sbin/halt mail /sbin/nologin operator /sbin/nologin games /sbin/nologin ftp /sbin/nologin nobody /sbin/nologin systemd-network /sbin/nologin dbus / sbin / nologin polkitd / sbin / nologin the sshd / sbin / nologin postfix / sbin / nologin ajie / bin / the bash the chrony / sbin / nologin Deploy / bin / the bash Nginx / sbin / nologin # - minus sign is left-aligned, + plus number is right justified [the root @ localhost 5.11 ] # awk ' the BEGIN {the FS = ":" {} the printf "% -20s% -20s \ n-",. 1 $, $}. 7 ' / etc /passwd root /bin/bash bin /sbin/nologin daemon /sbin/nologin adm /sbin/nologin lp /sbin/nologin sync /bin/sync shutdown /sbin/shutdown halt /sbin/halt mail /sbin/nologin operator /sbin/nologin games /sbin/nologin ftp /sbin/nologin nobody /sbin/nologin systemd-network /sbin/nologin dbus /sbin/nologin polkitd /sbin/nologin sshd /sbin/nologin postfix /sbin/nologin ajie /bin/bash chrony /sbin/nologin deploy /bin/bash nginx /sbin/nologin