Simple bash functions library to say something to TeamCity. See https://confluence.jetbrains.com/display/TCDL/Build+Script+Interaction+with+TeamCity will only printout messages if running under TeamCity, otherwise nothing will be printed out.

teamcity_messages.sh

#!/usr/bin/env bash

# Documentation for TeamCity messages:
# https://confluence.jetbrains.com/display/TCDL/Build+Script+Interaction+with+TeamCity

function __tc_encode {
    # Only unicode characters are not supported
    echo -n "$1" | sed "s/\([|']\)/\|\1/g; s/\[/\|\[/g; s/\]/\|\]/g; s/\r/\|r/g;" | sed ':a;N;$!ba;s/\n/|n/g'
}

function __tc_echo {
    # Only print messages if running under TeamCity
    if [ -n "${TEAMCITY_VERSION}" ]; then
        echo "$1"
    fi
}

function __tc_message {
    __tc_echo "##teamcity[message text='$(__tc_encode "$2")' status='${1:-NORMAL}']"
}

function __tc_simple {
    __tc_echo "##teamcity[$1 '$(__tc_encode "$2")']"
}

function tc_message {
    __tc_message "NORMAL" "$1"
}

function tc_message_failure {
    __tc_message "FAILURE" "$1"
}

function tc_message_error {
    __tc_message "ERROR" "$1"
}

function tc_message_warning {
    __tc_message "WARNING" "$1"
}

function tc_message_normal {
    __tc_message "NORMAL" "$1"
}

function tc_block_open {
    __tc_echo "##teamcity[blockOpened name='$(__tc_encode "$1")']"
}

function tc_block_close {
    __tc_echo "##teamcity[blockClosed name='$(__tc_encode "$1")']"
}

function tc_progress {
    __tc_simple "progressMessage" "$1"
}

function tc_progress_start {
    __tc_simple "progressStart" "$1"
}

function tc_progress_finish {
    __tc_simple "progressFinish" "$1"
}

function tc_build_problem {
    # $1 - text (required)
    # $2 - identity (optional)
    if [ "$2" = "" ]; then
        __tc_echo "##teamcity[buildProblem description='$(__tc_encode "$1")']"
    else
        __tc_echo "##teamcity[buildProblem description='$(__tc_encode "$1")' identity='$(__tc_encode "$2")']"
    fi
}

function tc_build_status {
    # $1 - text (required)
    # $2 - status (optional)
    if [ "$2" = "" ]; then
        __tc_echo "##teamcity[buildStatus text='$(__tc_encode "$1")']"
    else
        __tc_echo "##teamcity[buildStatus text='$(__tc_encode "$1")' status='$(__tc_encode "$2")']"
    fi
}

function tc_build_number {
    __tc_simple "buildNumber" "$1"
}

function tc_set_parameter {
    __tc_echo "##teamcity[setParameter name='$(__tc_encode "$1")' value='$(__tc_encode "$2")']"
}

# Testing code
function __tc_unit_test()
{
    tc_block_open "Test block"
    tc_message "Test message"
    tc_message "$(echo -e "Test\nmultiline\n\rmessage")"
    tc_message "Test\nnon-multiline\n\rmessage"
    tc_message "Test
multiline
message"
    tc_block_close "Test block"

    tc_block_open 'Test "quoted"'
    tc_message "Test escaping ' | [ ]"
    tc_message "Test non-escaping \ / { }"
    tc_block_close 'Test "quoted"'

}

# If the script is being executed with "test" argument run the unit test.
[[ "${BASH_SOURCE[0]}" == "${0}" ]] && [[ "test" == "${1}" ]] && __tc_unit_test