diff options
| -rw-r--r-- | manual/stdio.texi | 21 |
1 files changed, 15 insertions, 6 deletions
diff --git a/manual/stdio.texi b/manual/stdio.texi index e3e3918731..0b030cf2d8 100644 --- a/manual/stdio.texi +++ b/manual/stdio.texi @@ -1613,6 +1613,9 @@ make_message (char *name, char *value) int nchars; @end group @group + if (buffer == NULL) + return NULL; + /* @r{Try to print in the allocated space.} */ nchars = snprintf (buffer, size, "value of %s is %s", name, value); @@ -1624,9 +1627,10 @@ make_message (char *name, char *value) how much space is needed.} */ buffer = (char *) xrealloc (buffer, nchars + 1); - /* @r{Try again.} */ - snprintf (buffer, size, "value of %s is %s", - name, value); + if (buffer != NULL) + /* @r{Try again.} */ + snprintf (buffer, size, "value of %s is %s", + name, value); @} /* @r{The last call worked, return the string.} */ return buffer; @@ -1659,6 +1663,10 @@ buffer you allocate in advance. The @var{ptr} argument should be the address of a @code{char *} object, and @code{asprintf} stores a pointer to the newly allocated string at that location. +The return value is the number of characters allocated for the buffer, or +less than zero if an error occured. Usually this means that the buffer +could not be allocated. + Here is how to use @code{asprintf} to get the same result as the @code{snprintf} example, but more easily: @@ -1669,7 +1677,8 @@ char * make_message (char *name, char *value) @{ char *result; - asprintf (&result, "value of %s is %s", name, value); + if (asprintf (&result, "value of %s is %s", name, value) < 0) + return NULL; return result; @} @end smallexample @@ -3084,7 +3093,7 @@ For more information about the descriptor-level I/O functions, see @node Error Recovery @section Recovering from errors -You may explicitly clear the error and EOF flags with the @code{clearerr} +You may explicitly clear the error and EOF flags with the @code{clearerr} function. @comment stdio.h @@ -3112,7 +3121,7 @@ always fail again in the same way. So usually it is best to give up and report the error to the user, rather than install complicated recovery logic. -One important exception is @code{EINTR} (@pxref{Interrupted Primitives}). +One important exception is @code{EINTR} (@pxref{Interrupted Primitives}). Many stream I/O implementations will treat it as an ordinary error, which can be quite inconvenient. You can avoid this hassle by installing all signals with the @code{SA_RESTART} flag. |