T

TEMP:The environment variable usually used by a program to find the directory in which to create temporary files. Other programs use the TMP variable in a similar way.

temporary file:A file that is created for use by a command while it is running. The file is usually deleted when the command is completed. Most programs create temporary files in the directory indicated by the TMP or TEMP environment variable.

terminate-and-stay-resident (TSR):A DOS program that remains in memory and is ready to respond to an interrupt.

ternary operator:An operator that takes three operands. For example, the C-language ? operator.

text file:A file containing only ASCII characters in the range of 1 to 127.

thread:An operating-system mechanism that allows more than one path of execution through the same instance of a program.

thread ID:The name or handle of a particular thread within a process.

thread of execution:The sequence of instructions executed by the CPU in a single logical stream. In DOS, there is only one thread of execution.

thunk:An interoverlay call in an overlaid DOS program.

time stamp:The time of the last write operation to the file. Sometimes the term time stamp refers to the combination of the date and time of the last write operation. Also called modification time.

tiny memory model:A program with a single segment holding both code and data, limited to 64K, with the extension .COM.

TMP:The environment variable usually used by a program to find the directory in which to create temporary files. Other programs use the TEMP variable in a similar way.

.TMP:The extension that is often used to indicate a temporary file.

toggle:A feature with two states. Often used to describe a command that turns a feature on if it is off, and off if it is on. When used as a verb, “toggle” means to reverse the state of a feature.

TOOLS.INI:A file that contains initialization information for Microsoft tools such as PWB, CodeView, and NMAKE.

trace:To execute a single line or instruction. The next source line is traced in Source mode and the next instruction is traced in Assembly mode. If the source line or instruction contains a function, procedure, or interrupt call, the first source line or instruction of the call is executed. CodeView is ready to execute the next instruc-tion inside the call. See also “program step.”

tracepoint:(obsolete) A breakpoint that is taken when an expression, variable, or range of memory changes. This is now a type of conditional breakpoint. See also “conditional breakpoint.”

TSR:See “terminate-and-stay-resident.”

.TXT:The extension for a text file.

type cast:An operation in which a value of one type is converted to a value of a different type.

type casting:Including a type specifier in parentheses in front of an expression to indicate the type of the expression's value.