tvar

tvar is a simple command-line tool written in C for storing and retrieving temporary variable data, such as the output of scans or scripts. All data is stored in /tmp/tvar.db and will be destroyed when the system is rebooted (as /tmp is cleared on restart on most Unix/Linux systems).

Features

• Store arbitrary data from stdin and get a unique numeric variable name (e.g., 101, 102, ...)
• Retrieve data by variable name
• List all stored variable names
• Data is temporary and will be lost after a system reboot

Usage

Store Data

Store the output of a command or any text:

echo "my secret data" | tvar
# Output: 101

The output (e.g., 101) is the variable name you can use to retrieve the data later.

Store Data with a Custom Variable Name

You can specify your own variable name (up to 7 characters) using -n:

echo "my secret data" | tvar -n myvar
# Output: myvar

If the name already exists, the command will exit with code 2 and print nothing.

Retrieve Data

Retrieve the data for a given variable name:

tvar -r 101
# Output: my secret data

If the variable does not exist, the command will exit with code 1 and print nothing.

List All Variables

List all currently stored variable names:

tvar -l
# Output:
# 101
# 102
# ...

Example Workflow

# Store the output of a scan and print the variable name
nmap -sV target.com | tvar
# Output: 101

# Store with a custom variable name
nmap -sV target.com | tvar -n scan1
# Output: scan1

# Print the scan result directly through the pipeline
tvar -r 101
# OR
tvar -r scan1

# List all stored variables
tvar -l

Help Menu (for README only)

Usage: tvar [OPTION]

  -l           List all stored variable names
  -r VAR       Read and print the data for variable VAR
  -n NAME      Store stdin as a variable with custom name NAME (up to 7 chars)

If no option is given, tvar reads from stdin, stores the data, and prints the new variable name.

Notes

• Data is stored in /tmp/tvar.db and will be lost after a system reboot.
• Variable names are sequential numbers starting from 101.
• Maximum 100 variables can be stored at a time.
• No help menu is printed by the program itself; see this README for usage.

Use Cases

• Store temporary scan results or command outputs for later retrieval in scripts.
• Share data between different shell sessions without writing custom temp files.

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Feel free to modify or extend tvar for your own needs!