Builds with modern compilers (Clang 17 and GCC 13 with C99 errors enabled) fail with following errors:
cpp.c:548:9: error: parameter 'ch' was not declared, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
548 | unchget(ch)
| ^
549 | {
tok_io.c:219:13: error: call to undeclared function 'atoi'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
219 | line = atoi(t->vstr->str); /* extract line number */
| ^
In file included from token1.c:11:
tok_io.c:488:13: error: call to undeclared library function 'strlen' with type 'unsigned long (const char *)'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
488 | if ((len = strlen(buf)) > 3)
| ^
tok_io.c:488:13: note: include the header <string> or explicitly provide a declaration for 'strlen'
Builds with modern compilers (Clang 17 and GCC 13 with C99 errors enabled) fail with following errors:
```
cpp.c:548:9: error: parameter 'ch' was not declared, defaults to 'int'; ISO C99 and later do not support implicit int [-Wimplicit-int]
548 | unchget(ch)
| ^
549 | {
```
```
tok_io.c:219:13: error: call to undeclared function 'atoi'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
219 | line = atoi(t->vstr->str); /* extract line number */
| ^
In file included from token1.c:11:
```
```
tok_io.c:488:13: error: call to undeclared library function 'strlen' with type 'unsigned long (const char *)'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
488 | if ((len = strlen(buf)) > 3)
| ^
tok_io.c:488:13: note: include the header <string> or explicitly provide a declaration for 'strlen'
```