Shell and if-related parameters

[ -a FILE ]	FILEtrue if it exists.
[ -b FILE ]	True if it FILE exists and is a block special file.
[ -c FILE ]	FILEtrue if a special file is present and is a word.
[ -d FILE ]	True if it FILE exists and is a directory.
[ -e FILE ]	FILEtrue if it exists.
[ -f FILE ]	True if it FILE exists and is an ordinary file.
[ -g FILE ]	FILEtrue if Sgid is present and has been set.
[ -h FILE ]	True if it FILE exists and is a symbolic connection.
[ -k FILE ]	True if the FILE sticky bit is present and has been set.
[ -p FILE ]	True if it FILE exists and is a name pipe (f if o).
[ -r FILE ]	True if it FILE exists and is readable.
[ -s FILE ]	FILEtrue if it exists and the size is not 0.
[ -t FD ]	True if the file descriptor is FD open and points to a terminal.
[ -u FILE ]	True if the FILE suid (set user ID) is present and set.
[ -w FILE ]	FILEtrue if FILE exists and is writable.
[ -x FILE ]	True if it FILE exists and is executable.
[ -O FILE ]	FILEtrue if it exists and is a valid user ID.
[ -G FILE ]	FILEtrue if it exists and is a valid user group.
[ -L FILE ]	True if it FILE exists and is a symbolic connection.
[ -N FILE ]	If FILE an and has been mod is present, if the IED since it is last read is true.
[ -S FILE ]	True if it FILE exists and is a socket.
[file1 -nt file2 ]	if file1 has been Changed more recently than file2 , or if file1 exists and file2 does not is true.
[file1 -ot file2 ]	if file1 than file2 to be old, or file2 exists and file1 The is true if it does not exist.
[ FILE1 -ef FILE2 ]	FILE1true if and FILE2 point to the same device and node number.
[ -o Optionname]	True if the shell option "optionname" is turned on.
[ -zSTRING]	"STRING" is true if the length is zero.
[ -nString] or [string]	Thelength of "STRING" is not 0 Non-zero is true.
[STRING1 = = STRING2]	If 2 strings are the same. "=" May is used instead of "= =" For strict POSIX compliance is true.
[STRING1! = STRING2]	True if the strings are not equal.
[STRING1 < STRING2]	If the "STRING1" sorts before "STRING2" lexicographically The current locale is true.
[STRING1 > STRING2]	If the "STRING1" sorts after "STRING2" lexicographically The current locale is true.
[ARG1 OP ARG2]	"OP" is one -eq of,,, -ne -lt -le , -gt or -ge . These arithmetic binary operators return True if "ARG1" is equal to, not equal to, less than, less than or equal to, g Reater than, or greater than or equal to "ARG2", respectively. "ARG1" and "ARG2" are integers.

Shell and if-related parameters