MKTEMP

Section: C Library Functions (3)
Updated: April 10, 1987
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NAME

mktemp, mkstemp - make a unique file name

SYNOPSIS

char *mktemp(template)
char *template;

mkstemp(template)
char *template;

DESCRIPTION

Mktemp creates a unique file name and returns the address of the template. The template should contain a file name with trailing X's, normally something like /tmp/tempXXXXXX. The X's are replaced by the current process number and/or a unique letter combination. Mkstemp makes the same replacement to the template but opens the template file and returns a file descriptor open for reading and writing. Mkstemp avoids the race between testing whether the file exists and opening it for use. The number of file name combinations mktemp and mkstemp will try depends on the number of X's placed on the end of the template; six X's will result in them trying roughly 26 ** 6 combinations.

DIAGNOSTICS

Mktemp returns NULL on failure, mkstemp returns -1 if no suitable file could be created.