"... In PAGE 5: ... This mechanism, which first was used in the context of Mach to implement interposition agents [Jon93], forms the basis for our Ufo implementation. Table1 lists examples of the above approaches, while Table 2 summarizes their limitations and identifies the context in which they can be applied. We wanted an approach which works with most existing applications without the need for recompiling, and more importantly, which can be used without requiring root access.... ..."

"... In PAGE 4: ... This mechanism, which first was used in the context of Mach to implement interposition agents [Jon93], forms the basis for our Ufo implementation. Table1 lists examples of the above approaches, while Table 2 summarizes their limitations and identifies the context in which they can be applied. We wanted an approach which works with most existing applications without the need for recompiling, and more importantly, which can be used without requiring root access.... ..."

"... In PAGE 4: ... This mechanism, which first was used in the context of Mach to implement interposition agents [Jon93], forms the basis for our Ufo implementation. Table1 lists examples of the above approaches, while Table 2 summarizes their limitations and identifies the context in which they can be applied. We wanted an approach which works with most existing applications without the need for recompiling, and more importantly, which can be used without requiring root access.... ..."

"... In PAGE 4: ... This mechanism, which first was used in the context of Mach to implement interposition agents [Jon93], forms the basis for our Ufo implementation. Table1 lists examples of the above approaches, while Table 2 summarizes their limitations and identifies the context in which they can be applied. We wanted an approach which works with most existing applications without the need for recompiling, and more importantly, which can be used without requiring root access.... ..."

"... In PAGE 7: ...ng System, release 6.5.3. In programs enhanced by our infrastructure we ex- pect to observe two e ects on performance: an in- crease in startup time due to extra processing, and some overhead during execution due to the addi- tional indirection. Results summarized in Table1 come from the aver- age of 4 executions of each benchmark, running on a dedicated processor of the machine, to minimize the e ects of cold start and interferences from other processes. This table shows, for each program, the number of statically available dynamically{linked references (static hooks), how many times these hooks are triggered at runtime (dynamic activation count), the elapsed time for the unmodi ed execu- tion environment (baseline), and the elapsed time when invoking the empty wrapper at every call.... In PAGE 7: ... This table shows, for each module, its static size in disk as well as the size of all the virtual memory regions required to hold its code and data within the process address space at run{time. The `count apos; extension has been used to compute the columns la- beled `hook counts apos; in Table1 , the `forward apos; exten- sion corresponds to the `forward apos; experiment, and the `monitoring apos; extension to the `monitoring apos; ex-... ..."

"... In PAGE 8: ...ng System, release 6.5.3. In programs enhanced by our infrastructure we ex- pect to observetwo e ects on performance: an in- crease in startup time due to extra processing, and some overhead during execution due to the addi- tional indirection. Results summarized in Table1 come from the aver- age of 4 executions of each benchmark, running on a dedicated processor of the machine, to minimize the e ects of cold start and interferences from other processes. This table shows, for each program, the number of statically available dynamically{linked references (static hooks), how many times these hooks are triggered at runtime (dynamic activation count), the elapsed time for the unmodi ed execu- tion environment (baseline), and the elapsed time when invoking the empty wrapper at every call.... In PAGE 8: ... This table shows, for each module, its static size in disk as well as the size of all the virtual memory regions required to hold its code and data within the process address space at run{time. The `count apos; extension has been used to compute the columns la- beled `hook counts apos;in Table1 , the `forward apos; exten- sion corresponds to the `forward apos; experiment, and the `monitoring apos; extension to the `monitoring apos; ex-... ..."

"... In PAGE 7: ...ng System, release 6.5.3. In programs enhanced by our infrastructure we ex- pect to observe two e ects on performance: an in- crease in startup time due to extra processing, and some overhead during execution due to the addi- tional indirection. Results summarized in Table1 come from the aver- age of 4 executions of each benchmark, running on a dedicated processor of the machine, to minimize the e ects of cold start and interferences from other processes. This table shows, for each program, the number of statically available dynamically{linked references (static hooks), how many times these hooks are triggered at runtime (dynamic activation count), the elapsed time for the unmodi ed execu- tion environment (baseline), and the elapsed time when invoking the empty wrapper at every call.... In PAGE 7: ... This table shows, for each module, its static size in disk as well as the size of all the virtual memory regions required to hold its code and data within the process address space at run{time. The `count apos; extension has been used to compute the columns la- beled `hook counts apos; in Table1 , the `forward apos; exten- sion corresponds to the `forward apos; experiment, and the `monitoring apos; extension to the `monitoring apos; ex-... ..."