Commands by relay (3)

  • # newline to space; the whack before dollar-underbar is required alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' " # newline to comma; the whack before dollar-underbar is required alias nl2,="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{,}, @F) , qq{\n};}' " PROMPT> cat /tmp/foo foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 # 'tr' does not give a newline after it run. Makes a messy commandline. PROMPT> cat /tmp/foo|tr "\n" ' ' foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 $PROMPT> tr "\n" ' ' /tmp/foo # 'tr' does not take arguements PROMPT> tr "\n" ' ' /tmp/foo tr: extra operand `/tmp/foo' Try `tr --help' for more information. # 'nl2space' is a filter and takes arguements, adds a newline after it runs. PROMPT> cat /tmp/foo| nl2space foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010 PROMPT> nl2space /tmp/foo foo-001 foo-002 foo-003 foo-004 foo-005 foo-006 foo-007 foo-008 foo-009 foo-010


    0
    alias nl2space="perl -ne 'push @F, \$_; END { chomp @F; print join(qq{ }, @F) , qq{\n};}' "
    relay · 2009-10-01 02:22:23 6
  • checkfor: have the shell check anything you're waiting for. 'while : ; do' is an infinite loop '$*' executes the command passed in 'sleep 5' - change for your tastes, sleep for 5 seconds bash, ksh, likely sh, maybe zsh Ctrl-c to break the loop Show Sample Output


    1
    function checkfor () { while :; do $*; sleep 5; done; }
    relay · 2009-09-03 19:35:42 6
  • fcd : file change directory A bash function that takes a fully qualified file path and cd's into the directory where it lives. Useful on the commadline when you have a file name in a variable and you'd like to cd to the directory to RCS check it in or look at other files associated with it. Will run on any ksh, bash, likely sh, maybe zsh. Show Sample Output


    1
    function fcd () { [ -f $1 ] && { cd $(dirname $1); } || { cd $1 ; } pwd }
    relay · 2009-09-03 18:58:13 11

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Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

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Display GCC Predefined Macros
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