spec > bonuses > redirections > 001-append-twice-outputs-together
A double right redirection opens the file with the oflag O_APPEND
, so that its size is not truncated to 0 and output is written at the end of file. If the file does not exist, it is created.
In this test, twice outputs are appended to the same file.
rm -f "new_file_stderr_and_stdout"
./write_on_stdout_and_stderr ${GLOBAL_TOKEN}_stdout ${GLOBAL_TOKEN}_stderr &>>new_file_stderr_and_stdout
expected_to_not match_regex "${GLOBAL_TOKEN}_stdout"
expected_to_not match_regex "${GLOBAL_TOKEN}_stderr"
expected_to create_file "new_file_stderr_and_stdout" matching_regex "${GLOBAL_TOKEN}_stdout$"
expected_to create_file "new_file_stderr_and_stdout" matching_regex "${GLOBAL_TOKEN}_stderr$"
The following variables may appear in this test:
- ${GLOBAL_INSTALLDIR} -> The installation directory of 42ShellTester
- ${GLOBAL_TMP_DIRECTORY} -> The temporary directory in which tests are executed
- ${GLOBAL_TOKEN} -> A token that changes value at launch time
- ${PATH} -> The standard environment variable PATH
- ${HOME} -> The standard environment variable HOME
The following binaries may appear in this test:
- ./display_env -> A binary that iterates on
**envp
and write each element on standard output. - ./display_program_name -> A binary that writes its name on standard ouput.
- ./display_pwd -> A binary that writes on standard output the absolute path of the current directory returned by
getcwd(3)
, encountered with the stringsPWD:
and:PWD
. - ./exit_with_status -> A binary that immediately exits with the status given as first argument.
- ./read_on_stdin -> A binary that reads on standard entry and write each line on standard output suffixed with the character
@
(e.g. same behavior ascat -e
and the newline character). Whenread(2)
returns-1
, then the stringSTDIN READ ERROR
is written on standard error. - ./sleep_and_exit_with_status -> A binary that sleeps for a duration in seconds given as first argument and then exits with status given as second argument.
- ./sleep_and_write_on_stderr -> A binary that sleeps for a duration in seconds given as first argument and then writes on STDERR the string given as second argument without EOL.
- ./write_all_arguments_on_stdout -> A binary that writes on standard output each argument separated by the symbol
@
. If no argument is given, it writes the string "nothing to be written on stdout". - ./write_on_stderr -> A binary that writes on standard error the first given argument (the same behavior as
echo
but with only one argument) and exits with an error status code given as second argument. If no argument is given, it writes the string "write on stderr" and exit with status1
. - ./write_on_stdout -> A binary that writes on standard output the first given argument (the same behavior as
echo
but with only one argument). If no argument is given, it writes the string "write on stdout". - ./write_on_stdout_and_stderr -> A binary that writes on standard output the first given argument, and writes on standard error the second given argument. If an argument is missing, it writes the strings "write on stdout" and "write on stderr".